I'm not quite sure of what you're trying to achieve here, but I can point out a serious misconception. Your function RenderContents(HtmlTextWriter) is supposed to render (part of) your control as HTML. This is the stuff that gets sent to the client.
When I look at your writer.Write statement though it seems you want to write out code like it is found on ASPX pages:
<ItemTemplate> <%# DataBinder.Eval(Container.DataItem, \"Merhaba\")%> </ItemTemplate>"
While this kind of code is fine on ASPX pages that are compiled and run on the server side it has nothing to do with HTML.
Maybe if you explained a little more what it is that you're trying to achieve we could offer even better advice!
Modification:
I think this is a link you should study thouroghly:
http://msdn.microsoft.com/en-us/library/zt27tfhy.aspx[
^]
End Modification
Best regards,
Manfred