MFC DLL Primer

Having created an (shared) MFC DLL Project using MSVC++ app wizard, I now want to implement a function that takes a string argument.

This dll will be called from a VB app, so I am also unsure as to whether the function declaration should be using VARIANTS...
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Do this
in UR dll
extern "C" __declspec(dllexport) ExportedFunction(LPSTR str);

ExportedFunction(LPSTR str)
             // str will have the value

remember it takes only null terminated string.
in vb U can initialize UR string with all 0 s and pass it
copy the value U want to pass
if U don't want to pass null terminated string then defin as follows
ExportedFunction(LPSTR str, int nLength)
where nLength U will be passing from vb's string length

Hope this helps

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jhattinghAuthor Commented:
It looks useful, but may I ask why the function is notmadeamember of the C...App class created by AppWizard?
Hi !!!
   Yes inpras is right.
If u want to export the class itself then u can make it member function of App class and export the class itself or just export the required function.
Make it a member function no problem
CDllStaticTextApp::ExportedFunction(LPSTR str)

in .h file declaration
      __declspec(dllexport) ExportedFunction(LPSTR str);

Hope this helps
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