FIX: ClassWizard Incorrectly Reads LPDISPATCH Params from .TLB

• The ClassWizard included with: - Microsoft Visual C++ for Windows, versions 1.5, 1.51, 1.52 - Microsoft Visual C++, 32-bit Edition, versions 2.0, 2.1

SYMPTOMS

ClassWizard generates improper COleDispatchDriver derived member functions for methods that contain one or more LPDISPATCH* parameters. Specifically, ClassWizard generates member functions using a LPDISPATCH parameter instead of LPDISPATCH*. In other words, the asterisk (*) is missing.

RESOLUTION

To correct this problem, you must edit the COleDispatchDriver derived member directly.

For example, assume there is a type library (.TLB file) for an object that supports a method that returns a void and accepts an LPDISPATCH* as its only parameter. When ClassWizard reads the .TLB file, it generates a new class from COleDispatchDriver. The method for the member function that returns a void and accepts an LPDISPATCH* parameter ends up with this incorrect definition:

   void ITestObject::TestMethod(LPDISPATCH lpDispPtr)
   {
      static BYTE BASED_CODE parms[] =
         VTS_DISPATCH;
      InvokeHelper(0x1, DISPATCH_METHOD, VT_EMPTY, NULL, parms,
         lpDispPtr);
   }

   void ITestObject::TestMethod(LPDISPATCH* lpDispPtr)
   {
      static BYTE BASED_CODE parms[] =
         VTS_PDISPATCH;
      InvokeHelper(0x1, DISPATCH_METHOD, VT_EMPTY, NULL, parms,
         lpDispPtr);
   }

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This was fixed in Visual C++ version 5.0.

Keywords          : vcfixlist500 WizardIss kbbuglist kbfixlist
Technology        : kbMfc kbole
Version           : 1.50 1.51 1.52 2.00 2.10
Platform          : NT WINDOWS
Issue type        : kbbug
Solution Type     : kbfix