Thursday, November 13, 2008 7:51 PM
Yonggang Meng
How to invoke PageMethods in MasterPage
I have a web project, in the project, there is a MasterPage and some WebContentPages.
In the MasterPage, there is a function, when you click a button, show or hide the left content.When you refresh or navigate other WebContentPage, the left content keeps its display style.
Here is my first solution:
MasterPage.Master:
<div id="left" style='<%=string.Format("display:{0}",GetToolbarDisplayFlag())%>'>
</div>
<div id="buttons_left">
<img alt="Move Left" onclick="switchView('left',this);" src='<%=GetImgSrc()%>' />
</div>
Remember to set the EnablePageMethods = "True"
MasterPage.Master.CS:
public string GetToolbarDisplayFlag()
{
return HttpContext.Current.Session["ToolbarDisplay"] == null ? "block" : HttpContext.Current.Session["ToolbarDisplay"].ToString();
}
public string GetImgSrc()
{
if(GetToolbarDisplayFlag() == string.Empty || GetToolbarDisplayFlag() == "block")
{
return "../App_Themes/images/s_left.gif";
}
return "../App_Themes/images/s_right.gif";
}
[WebMethod]public static void SetToolbarDisplayFlag(string flag)
{
HttpContext.Current.Session["ToolbarDisplay"] = flag;
}
JS:
function switchView(objname,current)
{
var obj = $get(objname);
if(obj.style.display=="block" || obj.style.display=="")
{
obj.style.display="none";
current.src ='../App_Themes/images/s_right.gif';
PageMethods.SetToolbarDisplayFlag("none",OnSucceeded,OnFailed);
}
else
{
obj.style.display="block";
current.src ='../App_Themes/images/s_left.gif';
PageMethods.SetToolbarDisplayFlag("block",OnSucceeded,OnFailed);
}
}
function OnSucceeded(result, userContext, methodName)
{
return;
}
function OnFailed(error, userContext, methodName)
{
return;
}
if (typeof(Sys) !== "undefined") Sys.Application.notifyScriptLoaded();
When you click the button, it will cause exception: PageMethods not defined.
This is because the method "SetToolbarDisplayFlag" Js invoke is in MasterPage, it seems PageMethods donot contain MasterPage methods.
So, my solution is move the method "SetToolbarDisplayFlag" from MasterPage to a base page called "PageBase" which inherited from System.Web.UI.Page, and each WebContentPage derived from PageBase.
PageBase.cs:
public class PageBase : Page
{
[WebMethod]
public static void SetToolbarDisplayFlag(string flag)
{
HttpContext.Current.Session["ToolbarDisplay"] = flag;
}
}
Now, you can invoke methods in MasterPage.
Filed under: C#, Asp.net, Web, Ajax, PageMethods