Manoj Karkera's Blog

Save and Display Images

Manoj karkera — Mon, 15 Feb 2010 12:47:29 GMT

Generally in forum users ask how to save images and display images at same time. So, this article explain how to do this. I will be using FileUpload control and Datalist control, to display uploaded images into grid. I will also do validation for uploaded only images extension at client side when upload button has been clicked. If extension does not support then an error message appears.

Download source code here.

Initially I created an method name as DisplayImages() where I map folder name Images. Then using DirectoryInfo class create an instance of that. With instance object I called method name GetFiles(), where I will get all images uploaded into that folder.

void DisplayImages()

{

string upFolder = MapPath("~/Images/");

DirectoryInfo dir = new DirectoryInfo(upFolder);

dlstImages.DataSource = dir.GetFiles();

dlstImages.DataBind();

}

Before uploading files, its necessary that we should validate only images extension file should be uploaded. That validation I had at client side. A method name IsValidateExtension() has been called at OnClientClick event of button upload.

function IsValidateExtension()

{

try

{

var Extension = /(.gif|.png|.jpg|.jpeg)$/i;

var FileName=document.getElementById("upImage").value;

if(FileName != null || FileName != "")

{

if (Extension.test(FileName))

{

return true;

}

else

{

document.getElementById("<%=lblError.ClientID%>").innerHTML = "File extension not supported";

return false;

}

catch(e)

{

alert(e.message);

}

HTML mark up looks like below one :-

<div>

<asp:Label ID="lblImageFile" Text="Image File:" AssociatedControlID="upImage" runat="server" />

<asp:FileUpload ID="upImage" runat="server" BackColor="White" ForeColor="#333333" />

<br />

<asp:Button ID="btnUpload" Text="Upload" OnClick="btnUpload_Click" OnClientClick="return IsValidateExtension();"

runat="server" BackColor="#99CCFF" ForeColor="Black" Font-Bold="False" Font-Italic="False"

Font-Names="Verdana" />

<br />

<asp:Label ID="lblError" ForeColor="Red" runat="server" />

<br />

<div>

<asp:DataList ID="dlstImages" RepeatColumns="3" runat="server">

<asp:Image ID="Image1" ImageUrl='<%# Eval("Name", "~/Images/{0}") %>' Style="width: 200px"

runat="server" />

<br />

<%# Eval("Name") %>

</ItemTemplate>

</asp:DataList>

</div>

Button upload at server side looks like below :-

protected void btnUpload_Click(object sender, EventArgs e)

{

if (upImage.HasFile)

{

String filePath = "~/Images/" + upImage.FileName;

upImage.SaveAs(MapPath(filePath));

DisplayImages();

}

Initially, screen looks like below. Note, if any images uploaded previously then that images will display in datalist.

On click of upload button, first it will validate, then save into folder name Images, and finally it will display images using method name DisplayImages(), which I already explain on top. Note, I use one property of Datalist named RepeateColumns to display three images per row.

I hope you like this article, download source of course has been given on top.

User desire page after login

Manoj karkera — Sat, 06 Feb 2010 06:44:11 GMT

Generally when we login it will redirect us to default page. But in case when we want to go to our desire page which we store in book mark. In that case, after login it will always redirect us to default page and not our desire page. So this article I will explain how to go to desire page instead of default page using Non-form authentication and Form authentication.

Download source code for Non-Form Authentication here

Download source for Form Authentication here.

1) Non-Form Authentication :-

For this I will create three pages, namely Login.aspx, Default.aspx and MyProfile.aspx. I guess, you might come to know from page names what it will do. To go user desire page, I have created an session variable name Session["DesirePage"], which will store an your current URL address. And in login page, I will check if this session is null or not. if not, Then it will redirect user to its desire page.

Login.aspx

My Login page looks like below one :-

protected void btnSumbit_Click(object sender, EventArgs e)

{

if (txtUserName.Text == "manojk" && txtPassword.Text == "manojk")

{

Session["UserName"] = txtUserName.Text;

if (Session["DesirePage"] != null)

{

Response.Redirect(Convert.ToString(Session["DesirePage"]));

}

else

{

Response.Redirect("Default.aspx"); ;

}

As mention in code, I will check session variable Session[“DesirePage”] if its null or not. after check it will go to necessary condition.

Note :- I am not doing database connect to check for user id and password, as main thing I want to explain how to go user desire page.

Default.aspx

In this page, I am not doing anything special just checking if session[“UserName”] is null or not.

protected void Page_Load(object sender, EventArgs e)

{

if (Session["UserName"] != null)

{

Response.Write(string.Format("welcome {0}, this is default page",Session["UserName"]));

}

else

{

Response.Redirect("Login.aspx");

}

Note, that here Session["DesirePage"] check its not required as its an default page.

MyProfile.aspx

protected void Page_Load(object sender, EventArgs e)

{

if (Session["UserName"] != null)

{

Response.Write(string.Format("welcome {0}, this is your profile page", Session["UserName"]));

}

else

{

Session["DesirePage"] = Request.RawUrl;

Response.Redirect("Login.aspx");

}

As you might notice in above code that I am assigning session[“DesirePage”] as Request.RawUrl. So, when you try to access MyProfile.aspx, and session[“UserName”] is null it will assign session[“DesirePage”] and then it will redirect to login page.

You can test this scenario by making MyProfile.aspx page as start up page.

2) Using Form Authentication :-

Using form authentication, I have to check one more step.. In form authentication, initially I have to check if Request.QueryString["ReturnUrl"] is null or not.

protected void btnSumbit_Click(object sender, EventArgs e)

{

if (txtUserName.Text == "manojk" && txtPassword.Text == "manojk")

{

Session["UserName"] = txtUserName.Text;

HttpCookie AuthCookie;

AuthCookie = FormsAuthentication.GetAuthCookie(txtUserName.Text, true);

AuthCookie.Expires = DateTime.Now.AddDays(10);

Response.Cookies.Add(AuthCookie);

if(Request.QueryString["ReturnUrl"] != null)

Response.Redirect(Request.QueryString["ReturnUrl"]);

else

{

if (Session["DesirePage"] != null)

Response.Redirect(Convert.ToString(Session["DesirePage"]));

else

Response.Redirect("Default.aspx"); ;

}

I hope you like this article, how to go directly to desire page once login. Download source code has been given on top.

Bulk Insert using GridView and Sql Server XML

Manoj karkera — Tue, 26 Jan 2010 05:57:53 GMT

As to my previous article, how to update bulk records. This is how to insert bulk records. More a less, its same only, But some what difference. As in bulk update we fetch records and display in grid. But in bulk insert, we have to first create an empty row for inserting bulk records.

Download source and store procedure script from here.

private void InsertEmptyRow()

{

DataTable dt = new DataTable();

DataRow dr = null;

dt.Columns.Add(new DataColumn("CustName", typeof(string)));

dt.Columns.Add(new DataColumn("CustPosition", typeof(string)));

dt.Columns.Add(new DataColumn("CustCity", typeof(string)));

dt.Columns.Add(new DataColumn("CustState", typeof(string)));

for (int i = 0; i < 5; i++)

{

dr = dt.NewRow();

dr["CustName"] = string.Empty;

dr["CustPosition"] = string.Empty;

dr["CustCity"] = string.Empty;

dr["CustState"] = string.Empty;

dt.Rows.Add(dr);

}

gvCustomer.DataSource = dt;

gvCustomer.DataBind();

}

As, you see above code I am creating five empty rows initially which is empty. This method I am calling at page load event.

Note :- I am creating only five empty rows, you can create as much required for your bulk insert according to your requirement

And one more difference between, Bulk update and bulk insert is that as we fetch all records for bulk update, so we don’t have empty rows, but in insert we have five empty rows. One more thing, Suppose we insert three rows and two rows empty what would happen ?. For that I am checking if name field is empty or not, else don’t insert.

StringBuilder sb = new StringBuilder();

sb.Append("<root>");

for (int i = 0; i < gvCustomer.Rows.Count; i++)

{

TextBox txtName = gvCustomer.Rows[i].FindControl("txtName") as TextBox;

TextBox txtPosition = gvCustomer.Rows[i].FindControl("txtPosition") as TextBox;

TextBox txtCity = gvCustomer.Rows[i].FindControl("txtCity") as TextBox;

TextBox txtState = gvCustomer.Rows[i].FindControl("txtState") as TextBox;

if(txtName.Text.Length != 0)

sb.Append("<row Name='" + txtName.Text.Trim() + "' Position='" + txtPosition.Text.Trim() +

"' City='" + txtCity.Text.Trim() + "' State='" + txtState.Text.Trim() + "'/>");

}

sb.Append("</root>");

As you see, I am checking txtName if length is more then zero then insert record else skip it. As other insert detail is simple.

string conStr = WebConfigurationManager.ConnectionStrings["BlogConnectionString"].ConnectionString;

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("InsertCustomer", con);

cmd.CommandType = CommandType.StoredProcedure;

cmd.Parameters.AddWithValue("@XMLCustomer", sb.ToString());

try

{

using (con)

{

con.Open();

cmd.ExecuteNonQuery();

}

lblError.Text = "Record(s) Inserted successfully";

lblError.ForeColor = System.Drawing.Color.Green;

}

catch (Exception ex)

{

lblError.Text = "Error Occured";

lblError.ForeColor = System.Drawing.Color.Red;

}

Store procedure also simple, just direct insert from XML structure what it consist, this is also difference between bulk update as in which we check in where condition of customer id matches or not

set ANSI_NULLS ON

set QUOTED_IDENTIFIER ON

CREATE PROCEDURE [dbo].[InsertCustomer]

(

@XMLCustomer XML

)

BEGIN

INSERT INTO CUSTOMER

(CustName,CustPosition,CustCity,CustState)

SELECT

TempCustomer.Item.value('@Name', 'VARCHAR(50)'),

TempCustomer.Item.value('@Position', 'VARCHAR(50)'),

TempCustomer.Item.value('@City', 'VARCHAR(50)'),

TempCustomer.Item.value('@State', 'VARCHAR(50)')

FROM @XMLCustomer.nodes('/root/row') AS TempCustomer(Item)

RETURN 0

END

Note :- In bulk update, we are passing customer id also, here its not required as it is auto increment.

Screen Shot 1 ( Before Insert)

Screen Shot 2 (After Insert)

I hope you like this article about how to insert bulk records at a time. Like to have a feedback on this article.

Enhancement :- Proper validation is required for inserting bulk records. Example which field should be mandatory and which should not be.

Bulk Update using Gridview and Sql Server XML

Manoj karkera — Sun, 24 Jan 2010 12:47:54 GMT

As we are know importance of opening and closing connection while using Database. Generally when we have some many records into database and have to update all record at same time, opening and closing connection for each transaction will give performance issue.

For this, we like to do an bulk update for all records, instead of single records. When we update record into bulk, its open only one connection. Here, in this article I will explain how to do bulk update using gridview and sql server xml. I will pass an XML from code behind and using in store procedure. In SP, I will use XML as data type. and will update into table.

Download source code and SP script here.

I will use Template column in Gridview. Template column, use Textbox control to display all records. Records are binding using Sql Data Source. A button has been used, for updating bulk records. Using Sql Server XML, I had learned from here.

HTML mark up look like below :-

<asp:GridView ID="gvCustomer" runat="server" AutoGenerateColumns="False" BackColor="White"

BorderColor="#999999" BorderWidth="1px" CellPadding="3" DataKeyNames="CustID"

DataSourceID="SqlDataSource1" GridLines="Vertical" BorderStyle="None" ShowFooter="True">

<asp:BoundField DataField="CustID" HeaderText="CustID" InsertVisible="False" ReadOnly="True" SortExpression="CustID" />

<asp:TemplateField HeaderText="Name" SortExpression="CustName">

<asp:TextBox ID="txtName" runat="server" Text='<%# Bind("CustName") %>' BorderStyle="Solid" BorderWidth="1px"/>

</ItemTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="Position" SortExpression="CustPosition">

<asp:TextBox ID="txtPosition" runat="server" Text='<%# Bind("CustPosition") %>' BorderStyle="Solid" BorderWidth="1px"/>

</ItemTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="City" SortExpression="CustCity">

<asp:TextBox ID="txtCity" runat="server" Text='<%# Bind("CustCity") %>' BorderStyle="Solid" BorderWidth="1px"/>

</ItemTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="State" SortExpression="CustState">

<asp:TextBox ID="txtState" runat="server" Text='<%# Bind("CustState") %>' BorderStyle="Solid" BorderWidth="1px"/>

</ItemTemplate>

</asp:TemplateField>

</Columns>

</asp:GridView>

<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:BlogConnectionString %>"

SelectCommand="SELECT * FROM [Customer]"></asp:SqlDataSource>

<asp:Button ID="btnUpdate" runat="server" Text="Update" OnClick="btnUpdate_Click" />

<br />

<asp:Label ID="lblError" runat="server"></asp:Label>

</div>

I had created an function named UpdateCustomer, what it will do is first iterate all gridview rows and append in stringbuilder object , which it will create an XML structure

StringBuilder sb = new StringBuilder();

sb.Append("<root>");

for (int i = 0; i < gvCustomer.Rows.Count; i++)

{

string CustID = gvCustomer.Rows[i].Cells[0].Text;

TextBox txtName = gvCustomer.Rows[i].FindControl("txtName") as TextBox;

TextBox txtPosition = gvCustomer.Rows[i].FindControl("txtPosition") as TextBox;

TextBox txtCity = gvCustomer.Rows[i].FindControl("txtCity") as TextBox;

TextBox txtState = gvCustomer.Rows[i].FindControl("txtState") as TextBox;

sb.Append("<row CustID='" + CustID + "' Name='" + txtName.Text.Trim() + "' Position='" + txtPosition.Text.Trim() +

"' City='" + txtCity.Text.Trim() + "' State='" + txtState.Text.Trim() + "'/>");

}

sb.Append("</root>");

Then, I will call usual Sql Connection, Sql Command, pass parameter to database.

string conStr = WebConfigurationManager.ConnectionStrings["BlogConnectionString"].ConnectionString;

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("UpdateCustomer", con);

cmd.CommandType = CommandType.StoredProcedure;

cmd.Parameters.AddWithValue("@XMLCustomer", sb.ToString());

try

{

using (con)

{

con.Open();

cmd.ExecuteNonQuery();

}

lblError.Text = "Record(s) updated successfully";

lblError.ForeColor = System.Drawing.Color.Green;

}

catch (Exception ex)

{

lblError.Text = "Error Occured";

lblError.ForeColor = System.Drawing.Color.Red ;

}

As mentioned above, I am passing string builder object in XML structure to store procedure. I had created UpdateCustomer store procedure, which mark up looks like below one :-

set ANSI_NULLS ON

set QUOTED_IDENTIFIER ON

ALTER PROCEDURE [dbo].[UpdateCustomer]

(

@XMLCustomer XML

)

BEGIN

UPDATE Customer

SET CustName=TempCustomer.Item.value('@Name', 'VARCHAR(50)'),

CustPosition=TempCustomer.Item.value('@Position', 'VARCHAR(50)'),

CustCity=TempCustomer.Item.value('@City', 'VARCHAR(50)'),

CustState=TempCustomer.Item.value('@State', 'VARCHAR(50)')

FROM @XMLCustomer.nodes('/root/row') AS TempCustomer(Item)

WHERE CustID=TempCustomer.Item.value('@CustID', 'INT')

RETURN 0

END

As mentioned above code, parameter has an XML data type. Which will update customer table from temporary table created from XML.

Screen Shot 1 (Before Update)

Screen Shot 2 ( After Update)

As you can see in second screen shot, I had update customer Name field with all surname prefix with first name. I hope you like this bulk update with gridview and sql server xml. Download source code available on top.

Display Ascending and Descending Image in Header for Sorting

Manoj karkera — Mon, 07 Dec 2009 16:05:03 GMT

In GridView control we can sort columns ascending and descending, when we click header column. But the problem is that you can’t figure out how the column is sorted. To give end-users an indication whether column is sorted ascending or descending, it could be useful to add arrows to the columns that will indicate how the column is sorted. We can use GridView RowDataBound event to manipulate the header of GridView . I had added an image next to column when header column has been clicked. The current row’s RowType property is checked to verify that the row is a header row.

Download Source Code here

protected void gvSorting_RowDataBound(object sender, GridViewRowEventArgs e)

{

if (e.Row.RowType == DataControlRowType.Header)

{

foreach (TableCell cell in e.Row.Cells)

{

LinkButton lbSorting = (LinkButton)cell.Controls[0] as LinkButton ;

Image sortImage = new Image();

if (lbSorting.Text == gvSorting.SortExpression)

{

if (gvSorting.SortDirection == SortDirection.Ascending)

{

sortImage.ImageUrl = "Images/asc.gif";

sortImage.ToolTip = "Ascending Order";

}

else

{

sortImage.ImageUrl = "Images/desc.gif";

sortImage.ToolTip = "Descending Order";

}

cell.Controls.Add(sortImage);

}

The LinkButton that is used to sort the column has the name of the column that should be sorted. The text of link button is the value of the specified SortExpression on a BoundField column, The GridView’s SortDirection property determines whether the sort direction is ascending or descending. Based on the direction, different images are added to the sorted column’s header. When you mouse over an Image, it will display which order image has been sorted, if end-user get confused.

Output looks like below check GridView’s header click :-

Hope you like this small trick to show end-user which sorted has been done. Full source code can be downloaded from link mention above.

Text and Value Pairs with AutoCompleteExtender and Display record in Gridview

Manoj karkera — Mon, 30 Nov 2009 16:03:53 GMT

We know how to use AutoComplete control to display suggestions as you enter text into a TextBox. However, as we know AutoComplete control only retrieves text and no values. In sort, AutoComplete only retrieves text and no IDs. You might be thinking what use of IDs ?. An example of where we have multiple tables and we store ID in foreign table instead of text. Consider a scenario, where you have to search for department name and for that particular department, you have to display its employee data from employee table and in that department id has been stored. For this you will store department ID into employee table. Here where Text and Value Pairs with AutoComplete control is useful.

Download Source Code here.

The AutoComplete contorl includes a static method named CreateAutoCompeleteItem() that returns a single string that represents a text and value pair. You can use this method when returning a string array from the GetSuggestions() method to include a primary key with each suggestion.

A TextBox control, however, can represent only a single value. In order to represent the ID of the selected text, you need to add a hidden form field to your page.You can update the value of the hidden field whenever a user selects a new suggestions

I will explain here part by part.

[System.Web.Services.WebMethod]

public static string[] GetSuggestions(string prefixText, int count)

{

try

{

string conStr;

conStr = WebConfigurationManager.ConnectionStrings["MyBlogConnectionString"].ConnectionString;

string sqlQuery = "SELECT [FirstName],[CustomerID] FROM [Customer] WHERE FirstName like @FirstName";

SqlConnection conn = new SqlConnection(conStr);

SqlCommand cmd=new SqlCommand(sqlQuery,conn);

cmd.Parameters.AddWithValue("@FirstName", prefixText + "%");

conn.Open();

SqlDataReader dr = cmd.ExecuteReader();

List<string> custList = new List<string>();

string custItem = string.Empty;

while (dr.Read())

{

custItem=AutoCompleteExtender.CreateAutoCompleteItem(dr[0].ToString(),dr[1].ToString());

custList.Add(custItem);

}

conn.Close();

dr.Close();

return custList.ToArray();

}

catch (Exception ex)

{

throw ex;

}

Instead of creating web service, I am creating into same page by adding [System.Web.Services.WebMethod]. In First part, with prefix I am fetching records and bind into DataReader. In Second part, I am looping datareader and calling the AutoCompelteExtender.CreateAutoCompleteItem() method and adding into List<string> collections variable custList, and returing array of customer.

The AutoComplete extender is declaration as below :-

<cc1:AutoCompleteExtender ID="ace" TargetControlID="txtCustName" ServiceMethod="GetSuggestions"

MinimumPrefixLength="1" OnClientItemSelected="ace_itemSelected" FirstRowSelected="true"

runat="server" />

The AutoCompelte extender control includes an OnClientItemSelected property. When a new suggestion is selected, the ace_itemSelected() JavaScript method executes.

The ace_ItemSelected() method updates the value of the HiddenField with the value of the selected suggestion. The JavaScript method looks like below :-

function ace_itemSelected(sender, e)

{

var hdCustID = $get('<%= hdCustID.ClientID %>');

hdCustID.value = e.get_value();

}

The second parameter passed to the JavaScript method includes a value property that represents the primary key of the selected suggestion. The primary key is assigned to the hidden field so that it can be read when the page is posted back to the server.

When you select a text, an OnTextChanged() event will occur and fetch record from database for that particular customer and display into grid. Code looks like below :-

protected void txtCustName_TextChanged(object sender, EventArgs e)

{

gvCustomer.DataSource= GetCustomerDetail(Convert.ToInt32(hdCustID.Value));

gvCustomer.DataBind();

}

public SqlDataReader GetCustomerDetail(int CustID)

{

try

{

string conStr;

conStr = WebConfigurationManager.ConnectionStrings["MyBlogConnectionString"].ConnectionString;

string sqlQuery = "SELECT CustomerID,FirstName,MiddleName,LastName,Desgination,Address,City,";

sqlQuery=sqlQuery + "State,Country FROM [Customer] WHERE CustomerID = @CustomerID";

SqlConnection conn = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand(sqlQuery, conn);

cmd.Parameters.AddWithValue("@CustomerID", CustID);

conn.Open();

return cmd.ExecuteReader(CommandBehavior.CloseConnection);

}

catch (Exception ex)

{

throw ex;

}

After selecting value from textbox, output look like below :-

I hope you like text/value pair with AutoComplete and display record into grid at same time. Feedback are welcome.

Effective Paging and Sorting using GridView – Part II

Manoj karkera — Tue, 24 Nov 2009 16:13:31 GMT

In my previous article, I have shown how to use effective paging and sorting using gridview and ObjectDataSource, where you have millions of records and display records in grid which will affect performance problem. Here, I am doing same but without using ObjectDataSource. Here, I will be binding grid manually using dataset.

Download Source Code here.

I will be passing three parameters to store procedure to get records. StartRowIndex, MaximumRows and SortExpression. StartRowIndex will be grid current page index, MaximumRows will be grid page size, And SortExpression will be use for sorting grid. I created GridBind() method which will bind data to grid, which will call method GetCustomer() of customer class. In this, I will be passing above mention three parameters. Code snippets looks like below one.

private void GridBind(int StartRowIndex, int MaximumRows, String SortExpression)

{

gvCustomer.DataSource = cust.GetCustomer(StartRowIndex, MaximumRows, SortExpression);

gvCustomer.DataBind();

}

I am using PagerTemplate to display pagination in grid. Where, I will display as First, Prev,Next and Last for navigation purpose.

<table>

<tr>

<td>

<asp:LinkButton ID="lnkFirst" Text="<< First" Visible="false" OnCommand="gvPaging_Click"

CommandArgument="First" ToolTip="First Page" runat="server" />

</td>

<td>

<asp:LinkButton ID="lnkPrevious" Text="< Prev" Visible="false" OnCommand="gvPaging_Click"

CommandArgument="Prev" ToolTip="Prev Page" runat="server" />

</td>

<td>

<asp:LinkButton OnCommand="gvPaging_Click" Visible="false" ID="lnkNext" Text="Next >"

CommandArgument="Next" ToolTip="Next Page" runat="server" />

</td>

<td>

<asp:LinkButton ID="lnkLast" Text="Last >>" Visible="false" OnCommand="gvPaging_Click"

CommandArgument="Last" ToolTip="Last Page" runat="server" />

</td>

</tr>

</table>

</PagerTemplate>

Just, one thing to note about PagerTemplate is that when you have record less or equal to grid page size. It won’t display PagerTemplate . For this purpose, we have to grid pre-Render method. Inside that we have to make BottomPagerRow visible true.

protected void gvCustomer_PreRender(object sender, EventArgs e)

{

gvCustomer.BottomPagerRow.Visible = true;

}

For navigation purpose, I am using OnCommand event for all 4 links button (i.e. :- First, Prev, Next and Last). A common method created gvPaging_click where all link button click event has been called. CommandArgument property has been used for determining which link button has been clicked.

protected void gvPaging_Click(object sender, CommandEventArgs e)

{

string sortExpression=ViewState["sortExpression"].ToString() + " " + ViewState["Sort"].ToString();

if (e.CommandArgument.Equals("First"))

{

pageIndex = 0;

ViewState["pageIndex"] = 0;

GridBind(pageIndex * gvCustomer.PageSize, gvCustomer.PageSize, sortExpression);

}

else if (e.CommandArgument.Equals("Next"))

{

ViewState["pageIndex"] = int.Parse(ViewState["pageIndex"].ToString()) + 1;

pageIndex = int.Parse(ViewState["pageIndex"].ToString());

GridBind(pageIndex * gvCustomer.PageSize, gvCustomer.PageSize, sortExpression);

}

else if (e.CommandArgument.Equals("Prev"))

{

ViewState["pageIndex"] = int.Parse(ViewState["pageIndex"].ToString()) - 1;

pageIndex = int.Parse(ViewState["pageIndex"].ToString());

previous = true;

GridBind(pageIndex * gvCustomer.PageSize, gvCustomer.PageSize, sortExpression);

}

else

{

decimal countRow = cust.GetCustomerCount();

int pageSize = int.Parse(Math.Ceiling((countRow / gvCustomer.PageSize)).ToString());

ViewState["pageIndex"] = pageSize -1;

pageIndex = pageSize -1;

GridBind(pageIndex * gvCustomer.PageSize, gvCustomer.PageSize, sortExpression);

}

ViewState["pageIndex"] will add its value depend on which link button has been clicked. Eg for First value will be 0, Prev and Next value will be –1 and +1 respectively for current page index. When last row has been clicked at that time, I am calling GetCustomerCount() method, which will count total number of records in Database. To, get the actual page count, its has been divided with grid page size.

To, make navigation link visible true and false, depends on which has been clicked, Grid Databound event has been used.

protected void gvCustomer_DataBound(object sender, EventArgs e)

{

decimal countRow = cust.GetCustomerCount();

int pageSize = int.Parse(Math.Ceiling((countRow / gvCustomer.PageSize)).ToString());

LinkButton lnkFirst = (LinkButton)gvCustomer.BottomPagerRow.FindControl("lnkFirst");

LinkButton lnkPrevious = (LinkButton)gvCustomer.BottomPagerRow.FindControl("lnkPrevious");

LinkButton lnkNext = (LinkButton)gvCustomer.BottomPagerRow.FindControl("lnkNext");

LinkButton lnkLast = (LinkButton)gvCustomer.BottomPagerRow.FindControl("lnkLast");

if (pageIndex == 0)

{

lnkNext.Visible = true;

lnkLast.Visible = true;

lnkFirst.Visible = false;

lnkPrevious.Visible = false;

}

else if (pageIndex == pageSize)

{

lnkFirst.Visible = true;

lnkPrevious.Visible = true;

lnkNext.Visible = false;

lnkLast.Visible = false;

}

else if (pageIndex >= 1 && pageIndex < (pageSize -1))

{

lnkFirst.Visible = true;

lnkPrevious.Visible = true;

lnkNext.Visible = true;

lnkLast.Visible = true;

}

else

{

if (previous)

{

lnkFirst.Visible = true;

lnkPrevious.Visible = true;

lnkNext.Visible = true;

lnkLast.Visible = true;

}

else

{

lnkFirst.Visible = true;

lnkPrevious.Visible = true;

lnkNext.Visible = false;

lnkLast.Visible = false;

}

Code is simple to understand, Just using find control, getting link button id. making link button visible true/false according which link button has been clicked. Just one problem I face in this is, when user click from Last navigation to previous navigation at that time it still shows only first and previous navigation link button but not all links. One work around I use is having boolean variable previous and assign its value whenever previous link button has been clicked.

For sorting, I am using grid view sorting event. SortExpression is used for which column has been sorted.

protected void gvCustomer_Sorting(object sender, GridViewSortEventArgs e)

{

ViewState["sortExpression"] = e.SortExpression;

string sortExpression = ViewState["sortExpression"].ToString() + " " + ViewState["Sort"].ToString();

if (ViewState["Sort"] as string == "ASC")

{

ViewState["Sort"] = "DESC";

}

else

{

ViewState["Sort"] = "ASC";

}

GridBind(int.Parse(ViewState["pageIndex"].ToString()), gvCustomer.PageSize, sortExpression);

}

Store Procedure is same as which I had used in previous article, you can check out here, how i used it. And, also I will be giving download link for this source code and sp script.

Screen Shot :-

I hope you will like this article about effective pagination and sorting without using ObjectDataSource.

Display Image From Database

Manoj karkera — Sun, 15 Nov 2009 13:11:59 GMT

In my previous article, I had mention how to insert image into Database. Here I will show how to display image from database.This article is regarding how to display image from database. I am using Http Handler to display image. I will pass user id from text box and on click of search button I will display image into Image control.

Download source code from here.

Http Handler code look like this :-

<%@ WebHandler Language="C#" Class="DisplayImage" %>

using System;

using System.Web;

using System.Data.SqlClient;

using System.Web.Configuration;

public class DisplayImage : IHttpHandler {

string conString = WebConfigurationManager.ConnectionStrings["MyBlogConnectionString"].ConnectionString;

public void ProcessRequest(HttpContext context)

{

SqlConnection con = new SqlConnection(conString);

SqlCommand cmd = new SqlCommand("SELECT UserImage FROM UserData WHERE UserID=@UserID", con);

cmd.Parameters.AddWithValue("@UserID", context.Request["UserID"]);

using (con)

{

con.Open();

Byte[] bytes = (Byte[])cmd.ExecuteScalar();

context.Response.ContentType = "image/gif";

context.Response.BinaryWrite(bytes);

}

public bool IsReusable

{

get

{

return false;

}

HTML mark up look like this

<div>

<asp:UpdatePanel ID="UpdatePanel1" runat="server">

<asp:Label ID="Label1" runat="server" Text="Enter User ID" />

<asp:TextBox ID="txtUserID" runat="server" /><br />

<asp:Button ID="btnSearch" runat="server" Text="Search" OnClick="btnSearch_Click" />

<br />

<asp:Image ID="imgUser" Visible="false" runat="server" />

</ContentTemplate>

</asp:UpdatePanel>

</div>

Button click event of search look like below :-

protected void btnSearch_Click(object sender, EventArgs e)

{

imgUser.ImageUrl = string.Format("DisplayImage.ashx?UserID={0}", txtUserID.Text);

imgUser.Visible = true;

}

I will be passing userid as query string into httphandler file and display image.

output look like below when click on search button

Just a simple and small article, hope you like it. Download source code has been attached.

Insert Image into Folder and Database

Manoj karkera — Sun, 08 Nov 2009 03:48:00 GMT

File Upload control enables users to upload file to web application. After the file is uploaded, user can store the file in system. Normally,user store the file either on the file system or in a database. I had explain both approach below.

Download source code and script here.

Save into Folder :-

Here, I will explain how you can upload images to an application by using the AsyncFileUpload file upload control. I already explain file upload in my previous article, but this will upload only images, allowed extension were (gif,png,jpg,jpeg).

HTML mark up looks like below :-

<div>

<cc1:ToolkitScriptManager runat="Server" EnablePartialRendering="true" ID="ScriptManager1" />

<cc1:AsyncFileUpload ID="afuUpload" OnUploadedComplete="afuUpload_UploadedComplete"

OnUploadedFileError="afuUpload_UploadedFileError" runat="server" OnClientUploadComplete="uploadComplete"

Width="400px" UploaderStyle="Modern" UploadingBackColor="#CCFFFF" ThrobberID="myThrobber" />

<asp:Label runat="server" ID="myThrobber" Style="display: none;">

</asp:Label>

<asp:Label ID="lblStatus" Font-Bold="true" runat="server" Text="Status:-" />

<asp:Label ID="lblSuccess" ForeColor="Green" runat="server" /><br />

</div>

<asp:Label ID="lblErrorStatus" Font-Bold="true" runat="server" Text="Status:-" />

<asp:Label ID="lblError" ForeColor="Red" runat="server" /><br />

</div>

AsyncFileUpload has javascript event named OnClientUploadComplete in this I am make validation for only uploaded images extension files. And also display whether images uploaded successfully or not. One more event named OnClientUploadError, is used if file fail to upload images. Javascript markup looks like below :-

function uploadError(sender, args) {

//Good practice to put try,catch block. it will avoid javascript error at window status.

try

{

$get("dvFileErrorInfo").style.display='block';

$get("dvFileInfo").style.display='none';

$get("<%=lblError.ClientID%>").innerHTML = "File Not Uploaded" + args.get_errorMessage();

}

catch(e)

{

alert(e.message);

}

function uploadComplete(sender, args) {

try

{

var fileExtension=args.get_fileName();

var gif =fileExtension.indexOf('.gif');

var png =fileExtension.indexOf('.png);

var jpg=fileExtension.indexOf('.jpg);

var jpeg=fileExtension.indexOf('.jpeg);

if(gif > 0 || png > 0 || jpg > 0 || jpeg > 0)

{

$get("dvFileInfo").style.display='block';

$get("dvFileErrorInfo").style.display='none';

$get("<%=lblSuccess.ClientID%>").innerHTML = "File Uploaded Successfully";

}

else

{

$get("dvFileErrorInfo").style.display='block';

$get("<%=lblError.ClientID%>").innerHTML = "Allowed File extension are {.gif,.png,.jpg,.jpeg} supported";

$get("dvFileInfo").style.display='none';

return;

}

catch(e)

{

alert(e.message);

}

above code is very simple, I am validating file extension with help of get_fileName() property of args, where I will get file name and indexOf() method is used where given file extension is valid or not.

For saving into folder, I will use AsyncFileUpload event OnUploadedComplete. I am validating and saving into given folder. Also used OnUploadedFileError if error occured while uploading file. Source code looks below :-

public void afuUpload_UploadedComplete(object sender, AsyncFileUploadEventArgs e)

{

try

{

string savePath = MapPath("~/Images/" + Path.GetFileName(e.filename));

/*Validation for file extension*/

bool gif =Path.GetExtension(e.filename).Contains(".gif");

bool png =Path.GetExtension(e.filename).Contains(".png");

bool jpg =Path.GetExtension(e.filename).Contains(".jpg");

bool jpeg =Path.GetExtension(e.filename).Contains(".jpeg");

if (gif || png || jpg || jpeg)

{

afuUpload.SaveAs(savePath);

}

else

{

return;

}

catch (Exception ex)

{

throw ex;

}

public void afuUpload_UploadedFileError(object sender, AsyncFileUploadEventArgs e)

{

//ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "error", "top.$get(\"" + lblErrorStatus.ClientID + "\").innerHTML = 'Error: " + e.statusMessage + "';", true);

}

If give file is valid then it will upload images into Images folder inside application.

output looks like below :-

Save into Database :-

File uploading into database is bit a complicated then file upload into folder. As in this one, we have create an table with datatype as image.

I created an table named UserData for saving images into Database. Screen shots below :-

User has to give userID (which is unique name for each user) and image path to upload into DB.

Here I will be using AsyncFileUpload to upload file. I am using OnClientUploadComplete of javascript, to validate file extension to insert only images into database. This will be validating before click on save button.

HTML mark up look like this one :-

<div>

<cc1:ToolkitScriptManager runat="Server" EnablePartialRendering="true" ID="ScriptManager1" />

<asp:UpdatePanel ID="UpdatePanel1" runat="server">

<table>

<tr>

<td>

<asp:Label ID="Label1" runat="server" Text="User ID" />

</td>

<td>

<asp:TextBox ID="txtUserID" runat="server" />

</td>

</tr>

<tr>

<td>

<asp:Label ID="Label2" runat="server" Text="Upload Image" />

</td>

<td>

<cc1:AsyncFileUpload ID="afuUpload" OnClientUploadComplete="uploadComplete" runat="server"

Width="300px" UploaderStyle="Modern" UploadingBackColor="#CCFFFF" />

<asp:Label runat="server" ID="myThrobber" Style="display: none;">

</asp:Label>

</td>

</tr>

<td>

<asp:Button ID="btnSave" runat="server" Text="Save" OnClick="btnSave_Click" />

</td>

</tr>

</table>

<asp:Label ID="lblMsg" ForeColor="Red" runat="server" /><br />

<asp:ObjectDataSource ID="User" TypeName="objUser" InsertMethod="InsertUserDetail"

runat="server">

<asp:ControlParameter Name="UserID" ControlID="txtUserID" PropertyName="Text" />

<asp:ControlParameter Name="UserImage" ControlID="afuUpload" PropertyName="FileBytes" />

</InsertParameters>

</asp:ObjectDataSource>

</ContentTemplate>

</asp:UpdatePanel>

</div>

AsyncFileUpload, OnClientUploadComplete event used for validating file upload at javascript side is same as folder upload which already explain above. So that part I has been skiped.

source code for saving into database look like below :-

protected void btnSave_Click(object sender, EventArgs e)

{

try

{

/*Validation for file extension*/

bool gif = Path.GetExtension(afuUpload.FileName).Contains(".gif");

bool png = Path.GetExtension(afuUpload.FileName).Contains(".png");

bool jpg = Path.GetExtension(afuUpload.FileName).Contains(".jpg");

bool jpeg = Path.GetExtension(afuUpload.FileName).Contains(".jpeg");

if (gif || png || jpg || jpeg)

{

User.Insert();

lblMsg.Text = "File Upload Successfully";

lblMsg.ForeColor = System.Drawing.Color.Green;

}

else

{

lblMsg.Text = "Valid File Extension allowed are {.gif,.png,jpg,.jpeg}";

lblMsg.ForeColor = System.Drawing.Color.Red;

}

catch (Exception ex)

{

lblMsg.Text = "File Not Upload";

lblMsg.ForeColor = System.Drawing.Color.Red;

}

Class file objUser.cs looks like below :-

using System;

using System.Data;

using System.Data.SqlClient;

using System.Web.Configuration;

using System.Web.UI.WebControls;

/// <summary>

/// Summary description for objCustomer

/// </summary>

public class objUser

{

private readonly string conStr;

public objUser()

{

conStr = WebConfigurationManager.ConnectionStrings["MyBlogConnectionString"].ConnectionString;

}

public void InsertUserDetail(string UserID, byte[] UserImage)

{

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("InsertUserDetail", con);

cmd.CommandType = CommandType.StoredProcedure;

SqlParameter param = new SqlParameter();

param.SqlDbType=SqlDbType.Image;

param.ParameterName = "@UserImage";

param.SqlValue = UserImage;

cmd.Parameters.AddWithValue("@UserID", UserID);

cmd.Parameters.Add(param);

using (con)

{

con.Open();

cmd.ExecuteNonQuery();

}

output looks like below one :-

I hope you like this article for Image upload into Folder and Database. Download link has been provided above to download source code and script . In the next article I will provide how to display images from folder as well as from database. Like to have your feedback in this. Your feedback will improve my next articles.

Enchancement :-

1) Uniqueness of user name has not been validated

2) Functionality has been given primary consideration, UI design has been given secondary. Can improve design side.

Effective Paging and Sorting Using GridView and ObjectDataSource – Part I

Manoj karkera — Wed, 04 Nov 2009 15:50:00 GMT

With ObjectDataSource, you can do paging and sorting very effectively in gridview. In real time, we have millions of records in database. At that time, when we have to fetch those records and display in grid will take more time which makes performance issue. For this purpose, objectDataSource provide an good option for using paging and sorting in gridview. I had taken help from asp.net book and modify some of things.

Download source code here.

Paging :-

Notice that the objectDataSource control includes as EnablePaging property that has value True. The ObjectDataSource also includes a SelectCountMethod property that represents the name of a method that retrieves a record count from the data source. Even when using data source paging, you still need to enable AllowPaging property to True and using PageSize property.

When an ObjectDataSource control has its EnablePaging property set to the value True, the ObjectDataSource passes additional parameters when calling the method represented by its SelectMethod property. The two additional parameters are named StartRowIndex and MaximumRows, this parameter will be added implicitly.

To improve performance, the GetCustomerCount() method attempts to retrieve the total count from server cache. If the record count cannot be retrieved from the cache, the count is retrieved from the DB.

At store procedure side, we can use Row_Number() function to select a range of rows. Note that Row_Number() available above Sql Server 2005 versions only.

Property Use for paging in ObjectDataSource is SelectCountMethod and EnablePaging.

here more logic is at store procedure side then coding side. So mainly I will explain store procedure. and provide code at the end.

WITH CustDetails AS

(

SELECT CustomerID, ROW_NUMBER() OVER (ORDER BY CustomerID) AS RowNo

FROM CUSTOMER

)

SELECT

Customer.CustomerID,

Customer.FirstName,

Customer.MiddleName,

Customer.LastName,

Customer.Desgination,

Customer.Address,

Customer.City,

Customer.State,

Customer.Country

FROM

CustDetails

INNER JOIN

Customer

CustDetails.CustomerID = Customer.CustomerID

WHERE (RowNo BETWEEN @StartRowIndex + 1 AND @StartRowIndex + @MaximumRows + 1)

with clause is used for getting customer details with ROW_NUMBER() function to get row number wise. Then finally using inner join with CET table and customer table and fetching row that has been passed in SP between @StartRowIndex and @MaximumRows.

Sorting :-

For sorting, ObjectDataSource control includes a property named SortParameterName. Note, this is just the portion of the query for sorting. You can download full store procedure script which link has been given below.

SELECT

Customer.CustomerID,

Customer.FirstName,

Customer.MiddleName,

Customer.LastName,

Customer.Desgination,

Customer.Address,

Customer.City,

Customer.State,

Customer.Country

FROM

CustDetails

INNER JOIN

Customer

CustDetails.CustomerID = Customer.CustomerID

ORDER BY

CASE WHEN @SortExpression='CustomerID' THEN Customer.CustomerID END ASC,

CASE WHEN @SortExpression='CustomerID DESC' THEN Customer.CustomerID END DESC

Notice that the store procedure uses SQL CASE function to sort the records before they are added to query. Unfortunately, you can’t use a parameter with an ORDER BY clause, so the sort columns must be hard-coded in the CASE functions.

Html markup look for gridview look like below.

<div>

<asp:UpdatePanel ID="UpdatePanel1" runat="server">

<asp:GridView ID="gvPagingSorting" DataSourceID="Customer" AllowSorting="true" AllowPaging="true"

PageSize="5" DataKeyNames="CustomerID" runat="server" CellPadding="4" ForeColor="#333333"

GridLines="None">

</asp:GridView>

<asp:ObjectDataSource ID="Customer" TypeName="ObjCustomer" SortParameterName="SortExpression"

SelectCountMethod="GetCustomerCount" EnablePaging="true" SelectMethod="GetCustomer"

runat="server"/>

</ContentTemplate>

</asp:UpdatePanel>

</div>

objCustomer class look like below

using System;

using System.Web;

using System.Data;

using System.Data.SqlClient;

using System.Web.Configuration;

public class ObjCustomer

{

private readonly string conStr;

public ObjCustomer()

{

conStr = WebConfigurationManager.ConnectionStrings["MyBlogConnectionString"].ConnectionString;

}

public SqlDataReader GetCustomer(int StartRowIndex, int MaximumRows, String SortExpression)

{

try

{

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("GetCustomer", con);

cmd.CommandType = CommandType.StoredProcedure;

cmd.Parameters.AddWithValue("@StartRowIndex",StartRowIndex);

cmd.Parameters.AddWithValue("@MaximumRows",MaximumRows);

cmd.Parameters.AddWithValue("@SortExpression", SortExpression);

con.Open();

return cmd.ExecuteReader(CommandBehavior.CloseConnection);

}

catch (Exception ex)

{

throw ex;

}

public int GetCustomerCount()

{

try

{

HttpContext context = HttpContext.Current;

if (context.Cache["CustomerCount"] == null)

{

SqlConnection con = new SqlConnection(conStr);

string sqlQuery = "SELECT COUNT(CUSTOMERID) FROM [Customer]";

SqlCommand cmd = new SqlCommand(sqlQuery, con);

cmd.Connection.Open();

context.Cache["CustomerCount"] = (int)cmd.ExecuteScalar(); ;

}

return (int)context.Cache["CustomerCount"];

}

catch (Exception ex)

{

throw ex;

}

Explanation of class file :-

GetCustomer() method pass three parameters, StartRowIndex, MaximumRows and SortExpression. First two parameter used for paging and last parameter used for sorting. GetCustomer() method used for ObjectDataSource property SelectMethod. GetCustomerCount() method used for getting total count for customer from DB. GetCustomerCount() method used for ObjectDataSource property SelectCountMethod.

Note :-
One important thing to note about GetCustomer() method is that, return type of method is SqlDataReader(forward-read only) which will also help in improving performance. Of course, returning only grid pagesize should not be major problem even if you use datatable or dataset. Just once I remember user asking question in asp.net forum, whether its possible paging with datareader ?. So, I think this is the answer.

Output looks like below :-

Hope you like this article.

Kindly Note down changes for this article made on 24th nov 2009

I had modify the store procedure to work correctly with sorting for all grid pages. Previously, only current page was sorting by that field for that particular page size. And, next page will sort again. So, I modify that store procedure which i change download link on top. And re-writing procedure down also

ALTER PROC [dbo].[GetCustomer]

(

@StartRowIndex INT,

@MaximumRows INT,

@SortExpression VARCHAR(100)

)

WITH CustDetails AS

(

SELECT CustomerID, ROW_NUMBER() OVER (ORDER BY

CASE WHEN @SortExpression='CustomerID' THEN Customer.CustomerID END ASC,

CASE WHEN @SortExpression='CustomerID DESC' THEN Customer.CustomerID END DESC,

CASE WHEN @SortExpression='FirstName' THEN Customer.FirstName END ASC,

CASE WHEN @SortExpression='FirstName DESC' THEN Customer.FirstName END DESC,

CASE WHEN @SortExpression='MiddleName' THEN Customer.MiddleName END ASC,

CASE WHEN @SortExpression='MiddleName DESC' THEN Customer.MiddleName END DESC,

CASE WHEN @SortExpression='LastName' THEN Customer.LastName END ASC,

CASE WHEN @SortExpression='LastName DESC' THEN Customer.LastName END DESC,

CASE WHEN @SortExpression='Desgination' THEN Customer.Desgination END ASC,

CASE WHEN @SortExpression='Desgination DESC' THEN Customer.Desgination END DESC,

CASE WHEN @SortExpression='Address' THEN Customer.Address END ASC,

CASE WHEN @SortExpression='Address DESC' THEN Customer.Address END DESC,

CASE WHEN @SortExpression='City' THEN Customer.City END ASC,

CASE WHEN @SortExpression='City DESC' THEN Customer.City END DESC,

CASE WHEN @SortExpression='State' THEN Customer.State END ASC,

CASE WHEN @SortExpression='State DESC' THEN Customer.State END DESC,

CASE WHEN @SortExpression='Country' THEN Customer.Country END ASC,

CASE WHEN @SortExpression='Country DESC' THEN Customer.Country END DESC) AS RowNo

FROM CUSTOMER

)

SELECT Customer.CustomerID,

Customer.FirstName,

Customer.MiddleName,

Customer.LastName,

Customer.Desgination,

Customer.Address,

Customer.City,

Customer.State,

Customer.Country

FROM CustDetails INNER JOIN

Customer ON CustDetails.CustomerID = Customer.CustomerID

WHERE (RowNo BETWEEN @StartRowIndex + 1 AND @StartRowIndex + @MaximumRows + 1)

Serial No in GridView

Manoj karkera — Sat, 31 Oct 2009 04:02:15 GMT

So many time this question has been asked in forum regarding serial No display in gridview. I just know one work around like this way. Not sure if anybody already posted this before. So, main logic is to add DataItemIndex with plus one in Template field.

<%# Container.DataItemIndex + 1 %>

html mark up look like this.

<asp:GridView ID="GridView1" runat="server" DataSourceID="objCustomer">

<asp:TemplateField HeaderText="Serial No">

<asp:Label ID="lblNo" runat="server" Text='<%# Container.DataItemIndex + 1 %>'/>

</ItemTemplate>

</asp:TemplateField>

</Columns>

</asp:GridView>

<asp:ObjectDataSource ID="objCustomer" TypeName="Customer" SelectMethod="GetCustomer"

runat="server" />

Out put look like below one :-

AsynFileUpload Control and its Validation

Manoj karkera — Fri, 16 Oct 2009 15:32:00 GMT

AsyncFileUpload is an ASP.NET AJAX Control that allows you asynchronously upload files to server. I got some of idea from here. In asp.net forum, people are ask query about any file upload control without postback ?. So here it is. For Below I will mention important property both for client side and serve side.

Download complete sample code here.

Important Properties use at client side as below :-

Client Side Property	Description
OnClientUploadComplete	function executed after the file successfully uploaded
OnClientUploadError	executed if the file uploading failed

Important Properties use at server side as below :-

Server Side Event	Description
OnUploadedComplete	when the file successfully uploaded
OnUploadedFileError	when the unloaded file is corrupted

Method used to save file at server is SaveAs().

Namespace required :-

using System;

using AjaxControlToolkit;

using System.IO;

One Property of AsynFileUpload I like to mention is about ThrobberID. This property is used to display indicator when file is being uploaded. You can add the image to your page and associate the image with the AsynFileUpload property ThrobberID. Note that image does not directly points to ThrobberID property, but it will points through Label control that contains the image (and the Label is hidden with display:none), during the file upload, the image is displayed. Code will be something like below.

<asp:Label runat="server" ID="myThrobber" Style="display: none;">

</asp:Label>

One more important thing to note about this AsynFileUpload is that, Update Panel is included inside that. So not required to include UpdatePanel. In sort, it does not matter if you put UpdatePanel or not for AsynFileUpload control.

In this demo, I will show you how to upload file to given path. And provide information about file as of File Name, File Size, Content Type and Status of file whether its success or not of uploaded file.

Simple Save in Path :-

HTML markup looks like below :-

<div>

<cc1:AsyncFileUpload ID="afuUpload" OnUploadedComplete="afuUpload_UploadedComplete"

OnUploadedFileError="afuUpload_UploadedFileError" runat="server" OnClientUploadComplete="uploadComplete"

Width="400px" UploaderStyle="Modern" UploadingBackColor="#CCFFFF" ThrobberID="myThrobber" />

<asp:Label runat="server" ID="myThrobber" Style="display: none;">

</asp:Label>

<br />

<asp:Label ID="lblStatus" Font-Bold="true" runat="server" Text="Status:-" />

<asp:Label ID="lblSuccess" ForeColor="Green" runat="server" /><br />

<asp:Label ID="lblFileName" Font-Bold="true" runat="server" Text="FileName :-" />

<asp:Label ID="lblFileNameDisplay" runat="server" /><br />

<asp:Label ID="lblFileSize" Font-Bold="true" runat="server" Text="File Size :- " />

<asp:Label ID="lblFileSizeDisplay" runat="server" /><br />

<asp:Label ID="lblContentType" Font-Bold="true" runat="server" Text="Content Type :-" />

<asp:Label ID="lblContentTypeDisplay" runat="server" /><br />

</div>

<asp:Label ID="lblErrorStatus" Font-Bold="true" runat="server" Text="Status:-" /><asp:Label

ID="lblError" ForeColor="Red" runat="server" /><br />

</div>

I will use JavaScript to display file information, OnClientUploadComplete event where you will get complete file information.

Property Name	Description
get_fileName()	Return File Name
get_length()	Return File Size
get_contentType()	Return File Content Type

JavaScript uploadError and uploadComplete looks like below one :-

Server Side code looks like below one :-

public void afuUpload_UploadedComplete(object sender, AsyncFileUploadEventArgs e)

{

try

{

string savePath = MapPath("~/Uploads/" + Path.GetFileName(e.filename));

afuUpload.SaveAs(savePath);

/*Remeber this below part won't work,so you have to use uploadComplete() of JavaScript where you will

get file information.*/

* lblSuccess.Text = e.state.ToString();

lblFileName.Text = Path.GetFileName(e.filename);

lblFileSize.Text = e.filesize;

lblContentType.Text = afuUpload.ContentType;

}

catch(Exception ex)

{

throw ex;

}

public void afuUpload_UploadedFileError(object sender, AsyncFileUploadEventArgs e)

{

//ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "error", "top.$get(\"" + lblErrorStatus.ClientID + "\").innerHTML =

'Error: " + e.statusMessage + "';", true);

}

If you want to display any information using OnUploadedComplete and OnUploadedFileError from server side, its not possible. One work around is that you use ScriptManager RegisterClientScriptBlock(). Commented part above on OnUploadedFileError is one way.

So output like below one :-

Validation with AsynFileUpload :-

Generally we like to validate or restrict user to upload only particular file extension (e.g. .jpg,.doc).I will do two kind of validation one for file extension and other for file size should not be more then restrict size Here, I will restrict user to not upload .doc file. More or less code will be same only of above, I just will write addition code which required for validation. However, from download sample code (link provided above) you can get two different files each for simple upload and validation pages.

For validation using AsynFileUpload, you have to validate at two place one at client side and server side.

1) Validation for File Extension :-

client side validation has been done at OnClientUploadComplete event.

server side validation done at OnUploadedComplete event.

public void afuUpload_UploadedComplete(object sender, AsyncFileUploadEventArgs e)

{

try

{

string savePath = MapPath("~/Uploads/" + Path.GetFileName(e.filename));

if (Path.GetExtension(e.filename).Contains(".doc"))

{

return;

}

afuUpload.SaveAs(savePath);

}

catch (Exception ex)

{

throw ex;

}

output as below :-

2) Validation for File Size :-

client side validation has been done at OnClientUploadComplete event.

server side validation done at OnUploadedComplete event.

public void afuUpload_UploadedComplete(object sender, AsyncFileUploadEventArgs e)

{

try

{

string savePath = MapPath("~/Uploads/" + Path.GetFileName(e.filename));

if (int.Parse(e.filesize) > 3000000)

{

return;

}

afuUpload.SaveAs(savePath);

}

catch (Exception ex)

{

throw ex;

}

Output like below :-

Hope you will like how to use AsynFileUpload control and how to validate it for particular file extension and file size. Like to hear your feedback for this. (Download source code link provided on top)

Insert,Update and Delete Using Grid View and ObjectDataSource

Manoj karkera — Sun, 11 Oct 2009 11:14:00 GMT

Here, I will demonstrate how to use ObjectDataSource with Grid view for Insert,Update and Delete functionality.

Download Complete Source Code and Store procedure Script here

Insert :-

I have used InsertParameters of ObjectDataSource for Inserting record into DB using Grid view. In grid view, footer has been used for inserting new row. Necessary text box and Button added to save record into Database. Screen looks like below one

I have explicitly mention Insert Parameters in ObjectDataSource. As CustomerID is an auto increment and Primary Key so no need to insert it. Otherwise I will get error “ObjectDataSource 'Customer' could not find a non-generic method 'InsertCustomer' that has parameters: FirstName, MiddleName, LastName, Desgination, Address, City, State, Country, CustomerID.” So its necessary to mention correct parameters. And I would like to suggest that its better to mention parameters explicitly.

Note :-
The ObjectDataSource uses reflection to match its parameters against the parameters of the method that its calls. The Order of the parameters does not matter and the case of the parameters does not matter. However, the one thing that does matter is the names of the parameters.

ObjectDataSource for InsertParameter looks like below one

<asp:Parameter Name="FirstName" />

<asp:Parameter Name="MiddleName" />

<asp:Parameter Name="LastName" />

<asp:Parameter Name="Desgination" />

<asp:Parameter Name="Address" />

<asp:Parameter Name="City" />

<asp:Parameter Name="State" />

<asp:Parameter Name="Country" />

</InsertParameters>

I will also pass InsertMethod property of ObjectDataSource,which will have an InsertCustomer method.

InsertCustomer method looks like below one :-

public void InsertCustomer(string FirstName, string MiddleName,

string LastName, string Desgination, string Address,

string City, string State, string Country)

{

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("InsertCustomer", con);

cmd.CommandType = CommandType.StoredProcedure;

//this check is necessary, when u don't pass any value as it will pass as [default] and will give error

if (string.IsNullOrEmpty(FirstName))

FirstName = string.Empty;

if (string.IsNullOrEmpty(LastName))

LastName = string.Empty;

if (string.IsNullOrEmpty(MiddleName))

MiddleName = string.Empty;

if (string.IsNullOrEmpty(Desgination))

Desgination = string.Empty;

if (string.IsNullOrEmpty(Address))

Address = string.Empty;

if (string.IsNullOrEmpty(City))

City = string.Empty;

if (string.IsNullOrEmpty(State))

State = string.Empty;

if (string.IsNullOrEmpty(Country))

Country = string.Empty;

cmd.Parameters.AddWithValue("@IV_FirstName", FirstName);

cmd.Parameters.AddWithValue("@IV_LastName", LastName);

cmd.Parameters.AddWithValue("@IV_MiddleName", MiddleName);

cmd.Parameters.AddWithValue("@IV_Desgination", Desgination);

cmd.Parameters.AddWithValue("@IV_Address", Address);

cmd.Parameters.AddWithValue("@IV_City", City);

cmd.Parameters.AddWithValue("@IV_State", State);

cmd.Parameters.AddWithValue("@IV_Country", Country);

using (con)

{

con.Open();

cmd.ExecuteNonQuery();

}

Button Save for inserting record.

//Insert record Save Button

protected void btnSave_Click(object sender, EventArgs e)

{

Customer.InsertParameters["FirstName"].DefaultValue = GetGridTextBoxValue("txtFirstName");

Customer.InsertParameters["MiddleName"].DefaultValue = GetGridTextBoxValue("txtMiddleName");

Customer.InsertParameters["LastName"].DefaultValue = GetGridTextBoxValue("txtLastName");

Customer.InsertParameters["Desgination"].DefaultValue= GetGridTextBoxValue("txtDesgination");

Customer.InsertParameters["Address"].DefaultValue = GetGridTextBoxValue("txtAddress");

Customer.InsertParameters["City"].DefaultValue = GetGridTextBoxValue("txtCity");

Customer.InsertParameters["State"].DefaultValue = GetGridTextBoxValue("txtState");

Customer.InsertParameters["Country"].DefaultValue = GetGridTextBoxValue("txtCountry");

Customer.Insert();

}

GetGridTextBoxValue function will get TextBox text value from footer row of respective column.

//Get TextBox value of GridView Footer Row

public string GetGridTextBoxValue(string txtID)

{

try

{

TextBox txt = (TextBox)gvCustomer.FooterRow.FindControl(txtID);

return txt.Text;

}

catch (Exception ex)

{

return string.Empty;

throw ex;

}

(whole HTML mark up I will show in end of page for better understanding and of course I will provide whole source code for download)

Update :-

The Grid View automatically add the update parameters to the ObjectDataSource control’s UpdateParameters collections. But as I am using TemplateField column (this is done because adding footer row for insert purpose). So I have to explicitly mention the UpdateParameters. Set AutoGenerateEditButton="True" of Gridview to show Edit link. Screen looks like below one

First row change into textbox, and on clicking on Upate link button it will save change record into DB.

ObjectDataSource for Update Parameters looks like below one :-

<asp:Parameter Name="FirstName" />

<asp:Parameter Name="MiddleName" />

<asp:Parameter Name="LastName" />

<asp:Parameter Name="Desgination" />

<asp:Parameter Name="Address" />

<asp:Parameter Name="City" />

<asp:Parameter Name="State" />

<asp:Parameter Name="Country" />

<asp:Parameter Name="CustomerID" />

</UpdateParameters>

UpdateMethod property of ObjectDataSource,which will have an UpdateCustomer method.

UpdateCustomer method looks like below one :-

public void UpdateCustomer(int CustomerID, string FirstName, string MiddleName,

string LastName, string Desgination, string Address,

string City, string State, string Country)

{

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("UpdateCustomer", con);

cmd.CommandType = CommandType.StoredProcedure;

//this check is necessary, when u don't pass any value as it will pass [default].

//and will give error

if (string.IsNullOrEmpty(FirstName))

FirstName = string.Empty;

if (string.IsNullOrEmpty(LastName))

LastName = string.Empty;

if (string.IsNullOrEmpty(MiddleName))

MiddleName = string.Empty;

if (string.IsNullOrEmpty(Desgination))

Desgination = string.Empty;

if (string.IsNullOrEmpty(Address))

Address = string.Empty;

if (string.IsNullOrEmpty(City))

City = string.Empty;

if (string.IsNullOrEmpty(State))

State = string.Empty;

if (string.IsNullOrEmpty(Country))

Country = string.Empty;

// Add parameters

cmd.Parameters.AddWithValue("@IV_FirstName", FirstName);

cmd.Parameters.AddWithValue("@IV_LastName", LastName);

cmd.Parameters.AddWithValue("@IV_MiddleName", MiddleName);

cmd.Parameters.AddWithValue("@IV_Desgination", Desgination);

cmd.Parameters.AddWithValue("@IV_Address", Address);

cmd.Parameters.AddWithValue("@IV_City", City);

cmd.Parameters.AddWithValue("@IV_State", State);

cmd.Parameters.AddWithValue("@IV_Country", Country);

cmd.Parameters.AddWithValue("@IV_CustomerID", CustomerID);

using (con)

{

con.Open();

cmd.ExecuteNonQuery();

}

For Update, I am using GridView RowCommand event and check for CommandName as Update. and will pass CommandArgument as RowIndex number for getting row number and get respective textbox id.

//RowCommand used for Update

protected void gvCustomer_RowCommand(object sender, GridViewCommandEventArgs e)

{

if (e.CommandName=="Update")

{

Label lblCustID = new Label();

lblCustID = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[1].Controls[1] as Label ;

TextBox txtFirstName = new TextBox();

txtFirstName=gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[2].Controls[1] as TextBox;

TextBox txtMiddleName = new TextBox();

txtMiddleName = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[3].Controls[1] as TextBox;

TextBox txtLastName = new TextBox();

txtLastName = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[4].Controls[1] as TextBox;

TextBox txtDesgination = new TextBox();

txtDesgination = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[5].Controls[1] as TextBox;

TextBox txtAddress = new TextBox();

txtAddress = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[6].Controls[1] as TextBox;

TextBox txtCity = new TextBox();

txtCity = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[7].Controls[1] as TextBox;

TextBox txtState = new TextBox();

txtState = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[8].Controls[1] as TextBox;

TextBox txtCountry = new TextBox();

txtCountry = gvCustomer.Rows[Convert.ToInt16(e.CommandArgument)].Cells[9].Controls[1] as TextBox;

Customer.UpdateParameters["FirstName"].DefaultValue = txtFirstName.Text ;

Customer.UpdateParameters["MiddleName"].DefaultValue = txtMiddleName.Text;

Customer.UpdateParameters["LastName"].DefaultValue = txtLastName.Text;

Customer.UpdateParameters["Desgination"].DefaultValue = txtDesgination.Text;

Customer.UpdateParameters["Address"].DefaultValue = txtAddress.Text;

Customer.UpdateParameters["City"].DefaultValue = txtCity.Text;

Customer.UpdateParameters["State"].DefaultValue = txtState.Text;

Customer.UpdateParameters["Country"].DefaultValue = txtCountry.Text;

Customer.UpdateParameters["CustomerID"].DefaultValue = lblCustID.Text ;

}

Delete :-

Same as Update Parameter. The Grid View automatically add the delete parameters to the ObjectDataSource control’s DeleteParameters collections. But here no need to mention it explicitly, as I don’t have to pass parameters other then CustomerID, which will take automatically as i mentioned above. Make AutoGenerateDeleteButton="True" of GridView.

Here, Just mention DeleteMethod of ObjectDataSource as DeleteCustomer.Screen Shot looks like below.

DeleteCustomer method looks like below one :-

public void DeleteCustomer(int CustomerID)

{

SqlConnection con = new SqlConnection(conStr);

SqlCommand cmd = new SqlCommand("DELETE FROM Customer WHERE CustomerID=@CustomerID", con);

// Add parameters

cmd.Parameters.AddWithValue("@CustomerID", CustomerID);

using (con)

{

con.Open();

cmd.ExecuteNonQuery();

}

Generally, when we delete a record we would like to prompt a message that do u want to delete record ?. As data are very important for any projects. Here, I am doing this with Gridview RowDataBound event. Where I will get an Delete button on cell zero. Here, one important thing to mention that before assigning onClientClick event check for button CommandName as “Delete'”. This is necessary because when you try to edit record you will get two links as Update and Cancel. So, if you don’t want to update record and click on cancel it will prompt message for deleting record However, it won’t delete record.

Gridview RowDataBound event looks like below one :-

protected void gvCustomer_RowDataBound(object sender, GridViewRowEventArgs e)

{

if (e.Row.RowType == DataControlRowType.DataRow)

{

LinkButton btnDelete = new LinkButton();

btnDelete = e.Row.Cells[0].Controls[2] as LinkButton;

//below check is necessary, else it will give problem while editing record.

if (btnDelete.CommandName =="Delete")

btnDelete.OnClientClick = "return confirm('do you want to delete ?');";

}

The complete HTML markup below.

<asp:GridView ID="gvCustomer" DataSourceID="Customer" DataKeyNames="CustomerID" AutoGenerateEditButton="True"

AutoGenerateDeleteButton="True" runat="server" ShowFooter="True" AutoGenerateColumns="false"

CellPadding="4" ForeColor="#333333" GridLines="None" onrowcommand="gvCustomer_RowCommand"

onrowdatabound="gvCustomer_RowDataBound">

<asp:TemplateField Visible="false" HeaderText="CustomerID" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblFirstName" runat="server" Text='<%#Eval("CustomerID")%>' />

</ItemTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="First Name" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblFirstName" runat="server" Text='<%#Eval("FirstName")%>' />

</ItemTemplate>

<asp:TextBox ID="txtFirstName" Width="90px" runat="server" Text='<%#Eval("FirstName")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtFirstName" Width="90px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="Middle Name" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblMiddleName" runat="server" Text='<%#Eval("MiddleName")%>' />

</ItemTemplate>

<asp:TextBox ID="txtMiddleName" Width="90px" runat="server" Text='<%#Eval("MiddleName")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtMiddleName" Width="90px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="LastName" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblLastName" runat="server" Text='<%#Eval("LastName")%>' />

</ItemTemplate>

<asp:TextBox ID="txtLastName" Width="90px" runat="server" Text='<%#Eval("LastName")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtLastName" Width="90px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="Desgination" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblDesgination" runat="server" Text='<%#Eval("Desgination")%>' />

</ItemTemplate>

<asp:TextBox ID="txtDesgination" Width="90px" runat="server" Text='<%#Eval("Desgination")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtDesgination" Width="90px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="Address" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblAddress" runat="server" Text='<%#Eval("Address")%>' />

</ItemTemplate>

<asp:TextBox ID="txtAddress" Width="90px" runat="server" Text='<%#Eval("Address")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtAddress" Width="90px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="City" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblCity" runat="server" Text='<%#Eval("City")%>' />

</ItemTemplate>

<asp:TextBox ID="txtCity" Width="80px" runat="server" Text='<%#Eval("City")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtCity" Width="80px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="State" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblState" runat="server" Text='<%#Eval("State")%>' />

</ItemTemplate>

<asp:TextBox ID="txtState" Width="70px" runat="server" Text='<%#Eval("State")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtState" Width="70px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField HeaderText="Country" HeaderStyle-HorizontalAlign="Left">

<asp:Label ID="lblCountry" runat="server" Text='<%#Eval("Country")%>' />

</ItemTemplate>

<asp:TextBox ID="txtCountry" Width="90px" runat="server" Text='<%#Eval("Country")%>' />

</EditItemTemplate>

<asp:TextBox ID="txtCountry" Width="90px" runat="server" />

</FooterTemplate>

</asp:TemplateField>

<asp:TemplateField>

<asp:Button ID="btnSave" runat="server" Text="Save" OnClick="btnSave_Click" />

</FooterTemplate>

</asp:TemplateField>

</Columns>

</asp:GridView>

<asp:ObjectDataSource ID="Customer" TypeName="ObjCustomer" SelectMethod="GetCustomer" UpdateMethod="UpdateCustomer" InsertMethod="InsertCustomer" DeleteMethod="DeleteCustomer" runat="server" >

<asp:Parameter Name="FirstName" />

<asp:Parameter Name="MiddleName" />

<asp:Parameter Name="LastName" />

<asp:Parameter Name="Desgination" />

<asp:Parameter Name="Address" />

<asp:Parameter Name="City" />

<asp:Parameter Name="State" />

<asp:Parameter Name="Country" />

</InsertParameters>

<asp:Parameter Name="FirstName" />

<asp:Parameter Name="MiddleName" />

<asp:Parameter Name="LastName" />

<asp:Parameter Name="Desgination" />

<asp:Parameter Name="Address" />

<asp:Parameter Name="City" />

<asp:Parameter Name="State" />

<asp:Parameter Name="Country" />

<asp:Parameter Name="CustomerID" />

</UpdateParameters>

</asp:ObjectDataSource>

Hope you like this article regarding how to use Insert,Update and Delete using ObjectDataSource and GridView. I have added necessary images and explain code at regular point, still if you find problem don’t forget to reply me I will help you in understanding code. (For better understanding I attached Source Code and Script which you can download from link provided at top).

ObjectDataSource using Filter

Manoj karkera — Sat, 03 Oct 2009 11:12:30 GMT

The Filter expression is applied to the data returned by the control’s select method. A filter is particularly useful when used with caching. You can load all the data into the cache and then apply different filters to the cached data.

Download complete source code here.

In below example, I am using Dropdown list to display customer State, and the Grid View displaying all matching state.

<asp:UpdatePanel ID="up1" runat="server">

Select State :-

<asp:DropDownList ID="ddlState"

DataSourceID="objState"

AppendDataBoundItems="true"

AutoPostBack="true" DataTextField="State"

DataValueField="State" runat="server" >

<asp:ListItem Text="--Select--" Value="0" />

</asp:DropDownList>

<asp:ObjectDataSource ID="objState" TypeName="ObjFilter" SelectMethod="GetState"

EnableCaching="true" CacheDuration="Infinite" runat="server" />

<br />

<asp:GridView ID="gvFilter" runat="server" AutoGenerateColumns="False" DataSourceID="objCustomer"

CellPadding="4" DataKeyNames="CustomerID" ForeColor="#333333" GridLines="None"

BorderStyle="Groove">

<asp:BoundField DataField="FirstName" HeaderText="FirstName" SortExpression="FirstName" />

<asp:BoundField DataField="LastName" HeaderText="LastName" SortExpression="LastName" />

<asp:BoundField DataField="Desgination" HeaderText="Desgination" SortExpression="Desgination" />

<asp:BoundField DataField="Address" HeaderText="Address" SortExpression="Address" />

<asp:BoundField DataField="City" HeaderText="City" SortExpression="City" />

<asp:BoundField DataField="State" HeaderText="State" SortExpression="State" />

<asp:BoundField DataField="Country" HeaderText="Country" SortExpression="Country" />

</Columns>

</asp:GridView>

<asp:ObjectDataSource ID="objCustomer" runat="server" EnableCaching="true" CacheDuration="Infinite"

TypeName="ObjFilter" SelectMethod="GetCustomer"

FilterExpression="[State]='{0}'" onfiltering="objCustomer_Filtering">

<asp:ControlParameter Name="State" ControlID="ddlState" />

</FilterParameters>

</asp:ObjectDataSource>

</ContentTemplate>

</asp:UpdatePanel>

However, one thing to note about this is that, initially dropdown will have value as “0” text as “—Select—“. In that case we can perform operation on ObjectDataSource Filtering event. We can get the Filter value from e.ParameterValues[0], so if value is 0 then I can assign an default value as e.ParameterValues[0] = "AP"; or I can cancel existing filtering using e.Cancel.

protected void objCustomer_Filtering(object sender, ObjectDataSourceFilteringEventArgs e)

{

if (Convert.ToString(e.ParameterValues[0]) == "0")

{

/*Assinging Default value if not selected from dropdown list*/

//e.ParameterValues[0] = "AP";

/* You can also cancel filter if you don't want to continue your filter*/

//e.Cancel = true;

}

ObjFilter.cs class looks like below one :-

using System;

using System.Data;

using System.Data.SqlClient;

using System.Web.Configuration;

public class ObjFilter

{

private readonly string conStr;

public ObjFilter()

{

conStr = WebConfigurationManager.ConnectionStrings["MyBlogConnectionString"].ConnectionString;

}

public DataSet GetCustomer()

{

string sqlQuery = "SELECT CustomerID,FirstName,LastName,Desgination,";

sqlQuery +="Address,City,State,Country FROM Customer";

SqlDataAdapter da = new SqlDataAdapter(sqlQuery, conStr);

DataSet ds = new DataSet();

using (da)

{

da.Fill(ds);

}

return ds;

}

public DataSet GetState()

{

string sqlQuery = "SELECT DISTINCT State FROM Customer";

SqlDataAdapter da = new SqlDataAdapter(sqlQuery, conStr);

DataSet ds = new DataSet();

using (da)

{

da.Fill(ds);

}

return ds;

}

Output as below :-

Different Way of Using ObjectDataSource

Manoj karkera — Tue, 29 Sep 2009 14:32:00 GMT

The ObjectDataSource control enabled you to bind Data Bound controls such as Grid View,Details View and Form View controls to a component. You can use the ObjectDataSource control to easily build multi-tier applications with the ASP.NET Framework. The ObjectDataSource control enables you to cleanly separate your User Interface Layer from your Business Logic and Data Access Layers.

An ObjectDataSource control can represent any type of object in the .NET Framework. ObjectDataSource control use with collections,ADO.NET Data Reader, Dataset, LINQ to SQL queries and web services.

The ObjectDataSource control includes two properties named TypeName and SelectMethod in all below example. TypeName property contains the name of the component that you want to represent with the objectDataSource control. SelectMethod property represents the method of the component that you want to call when selecting data.

Download Complete Source code here

Using Collections :-

This is an simple collection example. Where its display an Customer Name using List collections.

ObjDSCollection class looks like below one

Using DataReader :-

The ADO.NET DataReader object provides you with a fast,read-only representation of database data. If you need to retrieve database

records in the fastest possible way, then you should use a DataReader object.

ObjDataReader class looks like below one :-

I had use three ADO.NET objects :- Connection,Command, and DataReader objects.Command object uses the connection object to connect to database. Then records are returned from command object and used by DataReader object. WebConfigurationManager is used to retrieve the database connection string from web configuration file.

Using DataSet :-

You also ca use the ObjectDataSource when you need to represent to ADO.NET DataSet. Using a DataSet is slower than using a DataReader.

However, you can perform advanced operations, such as filtering and sorting, on data represented with a DataSet.

ObjDataSet class looks like below one :-

Using LINQ :-

LINQ to SQL is the preferred method of data access in the .NET Framewor 3.5. You have to first create an CustomerLINQDataContext. The

easitest way to create the DataContext is to select LINQ to SQl Classes template. Go to menu-->Website-->Add New Item and select LINQ to SQL Classes template. Name the LINQ to SQl Classes CustomerLINQ.

ObjLINQ class looks like below one :-

Customer.dbml looks like below one.

Using Web Service :-

Web services enable you to share information across the Internet. When you communicate with a remote web service, you use a local proxy class

to represent the web service located on the remote machine. You can use the ObjectDataSource to represent this proxy class.

ObjWebService web service look like below :-

Output of all the above except Collection Demo is as below :-

I hope this will help you in using ObjectDataSource in different way.