What the heck is that? Can somebody explain?

I have studied subclassing in Java and I know OOPS fairly well. Only I have no experience of it with VB.

More specifically I want to extend the features of a textbox that's within an ActiveX control. Certain properties of the textbox, such as Multiline, Scrollbars etc. are unavailable even inside the ActiveX control as these are readonly at runtime. I want to manipulate them.

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