ASP.NET

<br />
[Designer("SM.WebControls.PagingControlDesigner"),<br />
 ParseChildren(false)]<br />
public class PagingControl : System.Web.UI.WebControls.WebControl,INamingContainer<br />
{<br />
   [Bindable(true),<br />
    EditorAttribute(typeof(UrlEditor), typeof(UITypeEditor))] <br />
   public string FirstButtonImg<br />
   {<br />
      get{return Convert.ToString(ViewState["FirstButtonImg"]);}<br />
      set{ViewState["FirstButtonImg"] = value;}<br />
   }<br />
 <br />
   protected PlaceHolder ParsedSubObjectContainer = new PlaceHolder();<br />
   protected override void CreateChildControls()<br />
   {<br />
       Panel Panel1 = new Panel();<br />
       Create some Controls and add to Panel1<br />
       Controls.Add(Panel1);<br />
       Controls.Add(ParsedSubObjectContainer);<br />
   }<br />
   protected override void AddParsedSubObject(Object obj)<br />
   {<br />
       ParsedSubObjectContainer.Controls.Add((Control)obj);<br />
   }<br />
<br />
   internal string GetDesignTimeHtml()<br />
   {<br />
      EnsureChildControls();<br />
      StringWriter sw = new StringWriter();<br />
      HtmlTextWriter writer = new HtmlTextWriter(sw);<br />
      this.RenderControl(writer);<br />
      return sw.ToString();<br />
   }<br />
   ...<br />
}<br />
public class PagingControlDesigner : ControlDesigner<br />
{<br />
   public override bool DesignTimeHtmlRequiresLoadComplete<br />
   {<br />
  	get{ return true;}<br />
   }<br />
<br />
   private PagingControl PagingControlInstance;<br />
<br />
   public override void Initialize(System.ComponentModel.IComponent component)<br />
   {<br />
      this.PagingControlInstance = (PagingControl) component;<br />
      base.Initialize (component);<br />
   }<br />
<br />
   public override string GetDesignTimeHtml() <br />
   {<br />
      return PagingControlInstance.GetDesignTimeHtml();<br />
   }<br />
   ...<br />
}<br />

<br />
<SM:PagingControl id="PagingControl1" runat="server" <br />
  FirstButtonImg='<%= Expression %>'<br />
><br />

<br />
<SM:PagingControl id="PagingControl1" runat="server"><br />
 <asp:DataGrid id="DataGrid1" runat="server"><br />
 </asp:DataGrid><br />
</SM:PagingControl><br />