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Problem calling API functions directly

chele
chele asked
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Medium Priority
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Last Modified: 2013-12-14
I am designing a user interface for Win 95 using Microsoft Visual C++ 5.0.  I have not been able to directly call an API function.  I have had no problem accessing them through the MFC library classes though.  For example, I used the CFileDialog class to implement a file open dialog box but when I tried calling the API function, GetOpenFileName() directly nothing happens during execution.  No compile or link error during build.  When I run the debugger and try to step into GetOpenFileName(), it was skipped over without even hitting the first internal line of code.  A call to GetOpenFileName() was in the assembly code when I checked.  Now, I need a simple audible ‘beep’ for my interface and I want to directly call another API function, Beep().  I haven’t found a MFC library class that encompasses Beep() so I am trying to call the API function directly.  Any ideas why I am having problems calling API functions directly?
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Engineer
Commented:
If you're in the context of a CWnd-derived class's functions, then you will need to use :: (scope resolution operator) to use the global functions.

For example, use ::GetOpenFileName() to call the global version (API version).

If you want a beep, take a look at the online help for ::MessageBeep(). You can pass a parameter for what types of beep you want.

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Commented:
Are you sure the API function is not executing?  Microsoft's debugger will not step into an API function.  This is to try to keep its workings secret (other debgers will, however.)  However the debugger will still run the function, it just won't step into it.  

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Commented:
Thanks again thui!
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