you must create your own control constructor that can provide verbs as custom menu items or user interface enhancements for the VS form designer.
Designer:
A class that takes care of the appearance and behavior of the control when placed in Visual Studio.NET. You can use this class to add new context menu verbs and, for ASP.NET controls, explicitly specify the HTML code that will be displayed in the designer.
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Custom Development Time Management Features in Visual Studio .NET
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