What happens when I DllImport a function that is not available on the runtime platform?

Question

I previously asked, How to determine the target of a symbolic link or Reparse Point? ...and got an answer that suggested the use of the Win32 function GetFinalPathNameByHandle, a function first available on Vista.

What happens if I build the .NET Assembly and then attempt to run it on WinXP, or WS2003, which does not have the GetFinalPathNameByHandle function? Is there a runtime exception, and if so, which one? Is there a way for me to handle that case in the app code?

score 7 · Accepted Answer · answered Feb 21 '10 at 16:20

7

You'll get an EntryPointNotFoundException when you call the method.

If the entire DLL file doesn't exist, you'll get a DllNotFoundException instead.

answered Feb 21 '10 at 16:20

SLaks

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And those exceptions are normal, catchable? – Cheeso Feb 21 '10 at 16:43
1

Yes. What makes you think they wouldn't be? – user200783 Feb 21 '10 at 16:52
Using LoadLibrary, GetProcAddress, FreeLibrary can avoid the exception. Not sure if that make sense if you can't support the functionality anyway. – Hans Passant Feb 21 '10 at 17:45

What happens when I DllImport a function that is not available on the runtime platform?

1 Answers1