How to reference a dll to Visual Studio without lib file

Question

I needed to add a third party library to my project, and they only supply a .dll file (no .lib)

I have added the dll to the project by going to the project Property Page under Common Properties -> References -> Add New Reference

I can see the dll under the External Dependencies folder in the Solution Explorer, so I guess it was included correctly.

But how do I reference the dll? When I try to add an instance variable (For example, MCC::iPort::ASCII iPort) to access the dll class, I get Error: name followed by '::' must be a class or namespace name, but I know thats the class name I can see it in the dll info under External Dependencies.

Answer 1

The only way to access a bare DLL without a .lib file is to load the DLL explicitly with LoadLibrary(), get pointers to the exported functions you want to access with GetProcAddress(), and then cast those pointers to the proper function signature. If the library exports C++ functions, the names you have to pass to GetProcAddress() will be mangled. You can list the exported names with dumpbin /exports your.dll.

extern "C" {
    typedef int (*the_func_ptr)( int param1, float param2 );
}

int main()
{
    auto hdl = LoadLibraryA( "SomeLibrary.dll" );
    if (hdl)
    {
        auto the_func = reinterpret_cast< the_func_ptr >( GetProcAddress( hdl, "the_func" ) );
        if (the_func)
            printf( "%d\n", the_func( 17, 43.7f ) );
        else
            printf( "no function\n" );

        FreeLibrary( hdl );
    }
    else
        printf( "no library\n" );

    return 0;
}

As has been noted by others, a LIB file can be created. Get the list of exported functions from dumpbin /exports your.dll:

ordinal hint RVA      name
      1    0 00001000 adler32
      2    1 00001350 adler32_combine
      3    2 00001510 compress
(etc.)

Put the names into a DEF file:

EXPORTS
adler32
adler32_combine
compress
(etc.)

Now make the LIB file:

lib /def:your.def /OUT:your.lib

For cases where the name has been decorated, either by C++ name mangling or 32-bit stdcall calling convention, simply copy and paste whatever names dumpbin reported, mangling and all.