<p>I'm just getting started with Custom User Controls in C# and I'm wondering if there are any examples out there of how to write one which accepts nested tags?</p>

<p>For example, when you create an <code>asp:repeater</code> you can add a nested tag for <code>itemtemplate</code>.</p>

I wrote a
blog post
about this some time ago. In brief, if you had a control with the following markup:
```
```
<Abc:CustomControlUno runat="server" ID="Control1">
    <Children>
        <Abc:Control1Child IntegerProperty="1" />
    </Children>
</Abc:CustomControlUno>
```
```
You'd need the code in the control to be along the lines of:
```
```
[ParseChildren(true)]
[PersistChildren(true)]
[ToolboxData("<{0}:CustomControlUno runat=server></{0}:CustomControlUno>")]
public class CustomControlUno : WebControl, INamingContainer
{
    private Control1ChildrenCollection _children;

    [PersistenceMode(PersistenceMode.InnerProperty)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public Control1ChildrenCollection Children
    {
        get
        {
            if (_children == null)
            {
                _children = new Control1ChildrenCollection();
            }
            return _children;
        }
    }
}

public class Control1ChildrenCollection : List<Control1Child>
{
}

public class Control1Child
{
    public int IntegerProperty { get; set; }
}
```
```