ASP.NET Inner Content with User Controls

Aug 272006

This was a real pain in the ass to figure out and searching around the internet, I couldn’t really find any straight answers. But I finally figured out how to use nested content with an ASP.NET User Control without resorting to a custom control. (Hey I’m a design-time guy.)

So let’s say you want to do this:

<uc1:Box runat="server" Title="This is cool!">
  <p>This would be child content of the box control.</p>
  <asp:Button runat="server" Text="This works too" />
</uc1:Box>

In Box.ascx, put this:

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="Box.ascx.cs" Inherits="Box" %>
<div id="BoxDiv" runat="server" class="box">
  <h3><asp:Literal id="TitleLiteral" runat="server"/></h3>
  <asp:PlaceHolder id="ChildPlaceHolder" runat="server" />
</div>

In Box.ascx.cs put this:

[ParseChildren( true, "ChildControls" )]
public partial class Box : System.Web.UI.UserControl
{

    public string Title
    {
        get
        {
            return TitleLiteral.Text;
        }
        set
        {
            TitleLiteral.Text = value;
        }
    }

    /// <summary>
    /// A collection of child controls nested in the user control's tags.
    /// </summary>
    public ControlCollection ChildControls
    {
        get
        {
            return ChildPlaceHolder.Controls;
        }
    }

}