If I understand your question, you've declared some custom events and you want to use it with existing WinForms controls. You cannot do it that way with WinForms. With WPF or Silverlight, you can use something called Attached Events. See
http://msdn.microsoft.com/en-us/library/bb613550.aspx[
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That said, you could derive your custom controls from existing Winforms controls, and then add your custom events to those classes. That may be something worth investigating to see if it will fit your specific requirements.