Thank you for contacting Telerik Support.
I had prepared a sample page for you, demonstrating how to create grammatically the RadDropDownList at code-behind and assign the client-side events. Please find it attached and let me know if any further assistance is needed.
Hope this would help. I will be glad to assist you any further.
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to the blog feed