.NET Interop IntPtr vs. ref

Question

Probably a noob question but interop isn\'t one of my strong points yet.

Aside from limiting the number of overloads is there any reason I should declare my DllImpo

Answer 1

I've had some fun cases where a parameter is something like ref Guid parent and the corresponding documentation says:

"Pointer to a GUID specifying the parent. Pass a null pointer to use [insert some system-defined item]."

If null (or IntPtr.Zero for IntPtr parameters) really is an invalid parameter, then you're fine using a ref parameter - maybe even better off since it's extra clear exactly what you need to pass.

If null is a valid parameter, you can pass ClassType instead of ref StructType. Objects of a reference type (class) are passed as a pointer, and they allow null.