PRB: AfxFindResourceHandle Fails w/ Icons, Cursors, & Strings

WINDOWS        | WINDOWS NT

The information in this article applies to:

• The Microsoft Foundation Classes (MFC) included with:

      - Microsoft Visual C++ for Windows, versions 1.5, 1.51, and 1.52
      - Microsoft Visual C++, 32-bit Edition, versions 2.0, 2.1, 2.2, 4.0
  

SYMPTOMS

AfxFindResourceHandle() fails when searching for icon (RT_ICON), cursor (RT_CURSOR), and string resources (RT_STRING).

CAUSE

This occurs because of how the Windows API function FindResource, which is called by AfxFindResourceHandle(), is designed.

RESOLUTION

For icons and cursors, use the RT_GROUP_ICON or RT_GROUP_CURSOR resource type with AfxFindResourceHandle() to return the EXE or DLL instance where the resource is located, and then call ::LoadIcon() or ::LoadCursor() to load the resource.

For string resources, call CString::LoadString(). It will search the EXE and MFC extension DLLs for the string resource, and load it into the CString.

STATUS

This behavior is by design.

MORE INFORMATION

AfxFindResourceHandle is an _AFXDLL-specific API for walking the resource list to look for a given match. It takes the name and type of a resource and returns the resource handle where it was first found (or NULL). It is documented in MFC Technote TN033: DLL Version of MFC.

Sample Code

The following sample code shows successful uses of RT_GROUP_ICON and RT_GROUP_CURSOR:

// This sample code can be placed in any MFC application or DLL
// that links with the DLL version of MFC. Create an icon with ID
// IDI_ICON1 and a cursor with ID IDC_CURSOR1. Call TestLoadIconCursor
// from CWinApp::Initinstance().

    return ::LoadIcon(AfxFindResourceHandle(lpIconName, RT_GROUP_ICON),
                      lpIconName);
}

    return ::LoadCursor(AfxFindResourceHandle(lpCursorName,
                        RT_GROUP_CURSOR),
                        lpCursorName);
}

void TestLoadIconCursor(void)

    HICON   hIcon;
    HCURSOR hCur;
    LPCTSTR lpcszRes;

    lpcszRes = MAKEINTRESOURCE(IDI_ICON1);
    hIcon = MyLoadIcon( lpcszRes );
    ASSERT (hIcon != NULL);

    lpcszRes = MAKEINTRESOURCE(IDC_CURSOR1);
    hCur = MyLoadCursor( lpcszRes );
    ASSERT (hCur != NULL);