My ATL com activex control not working in C# & VB .net

[Sunil George]

SUB: My ATL com activex control not working in C# & VB .net

Hello !
I have a ATL COM activex control developed in ATL 3.0 ( VS 6.0 ) . It works
fine in VB 6.0 but when I tested it in C# & VB .net . It gives error while
I drag & drop it from the toolbar. The error message is "Object refrence not
set to an instance of an object "
Please explain what wend wrong.

Thanks in advance.

From
Sunil George

 

[Dmitriy Lapshin [C# / .NET MVP]]

Hello Sunil,

Please tell what kind of ActiveX control have you created (Full Control or
Lightweight Control)? It might be that your control does not implement some
interfaces expected by VS .NET ActiveX wrapper generator or WinForms
designer (this is likely the case for lightweight controls).

I am pretty sure that an ATL 3.0 Full Control works fine within VS .NET
without any additional programming - I even was able to reach the control's
container and modify its window style (a kind of "Toolwindow" component
making its parent form looking and behaving like a toolwindow). That worked
fine in VB6 and in VS .NET.