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Inspecting COM / Interop class instance properly in VS.Net debugger?

Does anyone know if and how one can correctly see COM / Interop objects (in their correct type) in the VisualStudio debugger? All I get is the "evil" System .__ ComObject value (even if it identifies the type correctly)?

eg:.

Screenshot

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So, this is not an answer, but check these two screenshots. It's from the same app, just two different break points. In both cases, COM objects are from the same COM / AX library. I don't know why in one case I see "System .__ ComObject" and in the other the correct type. However, in both cases, I see the corresponding properties of the objects / interfaces. What gives? Why the difference?

The first one shows that it shows "System .__ ComObject", however it also shows me all the properties of the object. Click to view full size image.

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The second completely hides "System .__ ComObject". Click to view full size image.

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From .NET and COM: The Complete Compatibility Guide :

When an instance of a COM object is returned to you using the return type of a method or a parameter to reference, and the CLR cannot determine the type, you get the generic type System .__ ComObject because COM objects are always passed / returned as interface pointers.

You can try changing the return type with Marshal.CreateWrapperOfType

as shown in the following example:



MyType newObject = (MyType)Marshal.CreateWrapperOfType(oldObject, typeof(MyType))

Then you can look at newObject in the viewport and have the expected properties.

If the call fails, it throws an InvalidCastException.

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I used the direct window to manually query the properties of a COM object. The downside is that I don't think you are getting intellisense, so you need to know exactly what you want to test.

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