createinstancemacro.cpp

vc ADO 连接数据库

#import <msado15.dll> rename( "EOF", "adoEOF" )

struct InitOle {
InitOle()  { ::CoInitialize(NULL); }
~InitOle() { ::CoUninitialize();   }
} _init_InitOle_;

#define CREATEINSTANCE(sp,riid) \
    { HRESULT _hr =sp.CreateInstance( __uuidof( riid ) ); \
      if (FAILED(_hr)) _com_issue_error(_hr ); }


void main()
{
    HRESULT                hr    = S_OK;
    ADODB::_ConnectionPtr  Conn1 = NULL;

    CREATEINSTANCE( Conn1, ADODB::Connection )
    Conn1 = NULL;
    ::MessageBox( NULL, "Success!", "", MB_OK );
}