.NET Brain Droppings

Taking Custom Configuration Sections A Step Further

 Yup, it's cool, but it gets even cooler when you start writing your own configuration section handler implementations. The beauty of the configuration architecture is that it's completely extensible. To hook into the deserialization process all you need to do is implement a custom IConfigurationSectionHandler. The first time someone requests your named section via ConfigSettings::GetConfig, your implementation of IConfigurationSectionHandler::Create will be called and handed an XmlNode which you can then parse and turn into your own typed configuration object. This just opens infinite possibilities and builds upon the power of XML when it comes to embedding documents.

[From Drew's Blog]

Thanks Drew.  I kinda figured I'd only scratched the surface with this stuff.  Thanks, I'm gonna check out IConfigurationSectionHandler stuff.

[Currently Playing: Rancid - Life Won't Wait]

Custom configuration sections

Something I've found infinitely useful is custom configuration sections.  By using custom configuration sections, you are allowed to store a richer amount of information in the application config file, than when you simply add values to the <appSettings> section.

To add a custom config section, you must do 2 things: 1) declare the section group and section in the <configSections> portion of the app.config file, and 2) add the new sections to the config file.

To create a new section group that holds Vehicles add this code to your config file:

<configSections>

<sectionGroup name="Vehicles">

<section name="Honda" type="System.Configuration.NameValueSectionHandler,system, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, Custom=null" />

<section name="Nissan" type="System.Configuration.NameValueSectionHandler,system, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, Custom=null" />

</sectionGroup>

</configSections>

This code declares a new section group called Vehicles, which holds the sections Honda and Nissan.  It also declares that you will use the NameValueCollection object to get the information from the config file.

Next add the new configuration sections to your config file.  These sections are added to the same level as the <configuration> element.  Our new sections now look like this:

<Vehicles>

<Honda>

            <add key="Accord" value="Black" />

            <add key="Civic" value="Blue" />

      </Honda>

      <Nissan>

            <add key="Altima" value="Tan" />

            <add key="Pathfinder" value="Silver" />

</Vehicles>

Now that your config file has the appropriate values, you must write some code to get them out.  To do this, use the NameValueCollection object from the System.Collections.Specialized namespace.  This class is basically a HashTable object, with a couple more bells and whistles.

object o = ConfigurationSettings.GetConfig(“Vehicles/Honda);

Specialized.NameValueCollection col = o as Specialized.NameValueCollection;

if(o == null)

throw new ConfigurationException("Unable to load Honda section”);

Specialized.NameValueCollection.KeysCollection keys = col.Keys;

This code allows you to get all the keys for the NameValueCollection. You can then iterate over it using a for loop, extracting the values as you work your way through it.

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

{

      System.Console.WriteLine(col[i]);

}

[Currently Playing: Rage Against the Machine - Self-titled]

I did nothing this weekend...

Added HTTP Request code snippit

I'm adding a new category of posts to my blog; code snippits.  I was looking for a tool to manage code snippits when it hit me, why not post them to my blog.  I hope you find them useful.  I'll just randomly post stuff up there as I work on it. 

There are a couple problems with this.  One - the editor forces each line of code to have a <p/> break, so the code looks unweildy.  Two - Some of the code spans methods within a class, and I'm not quite sure how to post that yet.  I'll give this stuff some thought and hopefully have a fix soon.

For now, the first one is self-contained and was easy to post, it's an example of how to do a HTTP request and you can find it here.

[Currently Playing: Ministry - Animositisomina]