Base windows form, that takes a generic type

OK, so I'm trying to create a base Windows Form that implements the Singleton design pattern. I'm doing this because I'm building an MDI based application and I don't want a child control/form to exist more than once at a time.

I created a SingletonWindowsForm that extended System.Windows.Forms.Form and had a static method for GetInstance. I extended that form from each of my child controls but kept having problems with types. So at that point I added a type to the SingletonWindowsForm so I could specify which type should come back from the GetInstance method. However, I couldn't do "new T();" per the compiler. :)

Does anyone have a clue as to how I can go about doing this properly

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Base windows form, that takes a generic type

PhilipRieck
You simply need to declare the generic type with constriants:

Public Class Form1(Of T As New)

Public Shared Function Instance() As T

Return New T()

End Function

End Class

http://msdn.microsoft.com/library/default.asp url=/library/en-us/dnvs05/html/vb2005_generics.asp
bloodCLASSIQUE
I was on that path. I think what I missed was the type on the method itself. I'll try it tonight, thanks!
bud1024
You'll need to deal with the fact that the form might be closed by the user. Check this thread for an alternative approach.
Base windows form, that takes a generic type

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