子类化桌面窗口,explorer进程就崩溃.内存访问异常

子类化桌面窗口,explorer进程就崩溃.内存访问错误。

C/C++ code

    case DLL_PROCESS_ATTACH:        {            GetModuleFileName(NULL, FileName, sizeof(FileName));                        if (strstr(FileName, "explorer.exe"))            {                HWND hwnd = FindWindow("Progman", "Program Manager");                hwnd = FindWindowEx(hwnd, NULL, "SHELLDLL_DefView", NULL);                hwnd = FindWindowEx(hwnd, NULL, "SysListView32", "FolderView");                OldMsgProc = (WNDPROC)SetWindowLongPtr(hwnd, GWL_WNDPROC, (LONG)newMsgProc);            }        }LRESULT CALLBACK newMsgProc(HWND hDeskTop, UINT message, WPARAM wParam, LPARAM lParam){    switch(message)     {    case LVM_SETITEMPOSITION32:     case LVM_SETITEMPOSITION:        return 0;    default:        break;    }         //注释掉swithc语句块一样会崩溃    return CallWindowProc(OldMsgProc, hDeskTop, message, wParam, lParam);}

C/C++ code

return CallWindowProc(OldMsgProc, hDeskTop, message, wParam, lParam);