Question

I am looking for a link to instructions or a walkthru for Creating Custom Controls in Asp.net 3.5.

I have already looked at the following :

http://forums.asp.net/t/1385382.aspx : Turning an .ascx User Control into a Redistributable Custom Control asp.net 3.5

http://msdn.microsoft.com/en-us/library/aa479318.aspx : Turning an .ascx User Control into a Redistributable Custom Control asp.net 2.0

I think the two above links are for Composite Custom Controls which would be fine for now, as it seems it is easier to make a Composite rather than a full Custom control.

As per the instructions in the above link ( aa479318 ) , I created a user control MyControl.ascx file and published it, which was compiled it into a self contained .dll which was named App_Web_MyControl.ascx.cdcab7d2.

Then I put a

<%Register Assembly="App_Web_MyControl.ascx.cdcab7d2" 
              TagPrefix="cc" namespace="TheNamespace" %> 

in the aspx file (in another app) where I wanted to use the Custom Control, and I add a reference to the .dll assembly in the project.

The CustomControl name is not being recognized when I try creating it in the .aspx code by

<cc:MyControl ID="idname" runat="server" />

I get error Element ‘MyControl’ is not a known element.’

Answer 1

This is late, I know, but here goes..

I successfully turned an .ascx UserControl into a redistributable dll by doing this:

1. Created an ASP.NET Web Site project called AscxDll
2. Developed my UserControl in said project at this location:
   ~/App_UserControls/RadioButtonQuestion.ascx.

3. Published the Website project with only these settings ticked in the Publish Web Site dialog:

   Use fixed name and single page assemblies

   Emit debug information

4. Open VS cmd prompt and run:
   aspnet_merge “C:\PrecompiledWebOutputDir\AscxDll” -o AssemblyName -r
5. Copied the merged AssemblyName.dll to bin folder of another webapp/website project that needed it.
6. In client project’s web.config, added this to pages\controls
   <add tagPrefix=”MyPrefix” namespace=”ASP” assembly=”AssemblyName”/>
7. Added control to a web page in client project:
   <MyPrefix:app_usercontrols_radiobuttonquestion_ascx ID=”rbq1″ runat=”server” QuestionText=”Set by aspx source” />

Note how it is registered in web.config using namespace=”ASP”, and how the tag on the web page has a few underscores in it <MyPrefix:app_usercontrols_radiobuttonquestion_ascx />
This may be the key to where you’re going wrong?

This worked well for me, although it took me AGES to figure out. It’s probably easier to just build a server control or composite control, unless your UI is very complex.

Hope this helps somebody.