C# and void pointers

Question

I am writing my first C# application, but as luck would have it I must use void pointers (working with a DLL which returns handles). From what I read there are a few options:

1. Unsafe code, for example see http://www.c-sharpcorner.com/UploadFile/gregory_popek/WritingUnsafeCode11102005040251AM/WritingUnsafeCode.aspx

2. In the C# program writing in my function declerations IntPtr instead of void*. e.g.: public static extern char SupportsWhatever(IntPtr h);

3. Using ref, e.g.: public static extern char SupportsWhatever(ref h);

It should also be noted that I need to marshal information back and forth between the DLL and C# application.

The unsafe option was the first that popped up on Google, but for some reason writing the keyword unsafe before all my functions just doesn't feel right.

Any recommendations?

Answer 1

Typically, for marshaling situations, using IntPtr would be the preferred approach here. It is allowed in safe code, and makes it very clear that your intention is marshaling a pointer back and forth.

This is how much of the BCL represents handles. For example, you can construct a Cursor from an IntPtr representing the native handle.