You can use the EditorInitializing
event instead of the attribute:
sender, Telerik.WinControls.UI.EditorInitializingEventArgs e)
I hope this will be useful. Let me know if you have additional questions.
Telerik by Progress
Check out the Windows Forms project converter, which aids the conversion process from standard Windows Forms applications written in C# or VB to Telerik UI for WinForms.For more information check out this blog post
and share your thoughts.