ASP.NET 2.0 User Controls in App_Code
Here is a tip I picked up at the MVP summit from ASP.NET team member Simon Calvert.
You can place a user control file in App_Code, as long as the .ascx uses inline code. The user control will compile into the App_Code assembly. Instead of using LoadControl with a virtual path parameter, you can use the overloaded version accepting a Type parameter.
As an example, here is the contents of MyUserControl.ascx. Place the file in the App_Code directory.
<%@ Control Language="C#" ClassName="MyUserControl" %>
<script runat="server">
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
Label.Text = "Bonjour!";
}
</script>
<asp:Label runat="server" ID="Label" />
Here is the code for a web form that dynamically loads the control.
using System;
using ASP;
public partial class _Default : System.Web.UI.Page
{
protected override void OnInit(EventArgs e)
{
base.OnInit(e);
MyUserControl c;
c = LoadControl(typeof(MyUserControl), null)
as MyUserControl;
if (c != null)
{
Controls.Add(c);
}
}
}
Note: No @ Reference directive was required in the .aspx file.
Why is this interesting?
I was conversing with Shawn Wildermuth, and Shawn is unhappy with the solutions needed to make types visible in the ASP.NET 2.0 compilation model, solutions like using @ Reference and stubs. Shawn is not the only one. The above solution is easy if you don’t mind using the App_Code directory. The user control type will be visible to both the App_Code assembly and all web form assemblies.