Return value of CDialog::StaticDialogProc

erha
2009-09-11
2013-05-28
  • erha
    erha
    2009-09-11

    Hi David,

    I am encountering some problem here.
    As the return value of CDialog::StaticDialogProc and its related function (DialogProc, DialogProcDefault etc) is BOOL, the return value set by the object (which inherit from CDialog) is not pass to the Windows object as it is cast to BOOL.

    Is there any reason why it is declare as BOOL instead of LRESULT?

     
  • David
    David
    2009-09-15

    Hi,

    The return value of CDialog::StaticDialogProc is BOOL because thats the way the Windows API handles message processing for dialogs.

    Here is a quote regarding the return value of DialogProc from the Windows API documentation:

    "Typically, the dialog box procedure should return TRUE if it processed the message, and FALSE if it did not. If the dialog box procedure returns FALSE, the dialog manager performs the default dialog operation in response to the message.

    If the dialog box procedure processes a message that requires a specific return value, the dialog box procedure should set the desired return value by calling SetWindowLong(hwndDlg, DWL_MSGRESULT, lResult) immediately before returning TRUE. Note that you must call SetWindowLong immediately before returning TRUE; doing so earlier may result in the DWL_MSGRESULT value being overwritten by a nested dialog box message."

    Best Regards,
    David

     
  • erha
    erha
    2009-09-29

    Thanks for the info.

    Will try it….

    Thanks….