Is there generally a noticeable performance hit when calling PInvoke on Win32 / COM methods?

Question

I\'m wondering whether anyone has a decent explanation or overview on the negative aspects of using DLLImport / PInvoke on Win32 methods from managed .Net code?

I plan t

Answer 1

Here are some issues I see with PInvoke:

• Parameter marshaling can be expensive, depending on the data type (blittable / non-blittable)
• Correct parameter marshaling is often not very intuitive
• PInvoke does not provide any compile time security. One can easily misspell DLL or function names easily without the compiler complaining.

If you plan to use lots of unmanaged functions I would create a mixed DLL (http://msdn.microsoft.com/en-us/library/x0w2664k.aspx) rather than declaring a bunch of PInvokes.