Close dialog box, onclose and oncancel

We know that in the dialog box, you can choose to reload oncancel as a dummy function by blocking the ESC key and automatically Exit:

 

Void cxxxxdlg: oncancel ()
{
// Todo: add your specialized code here and/or call the base class

// Cdialog: oncancel (); // disable oncancel
}

However, in this way, closing the button in the upper right corner does not work, because when you click to close the button, you will automatically call cxxxxdlg: oncancel () L to close the dialog box, because cxxxxdlg:: The dialog box cannot be closed because nothing is done in oncancel. To modify this bug, you need to reload the onclose message function:

 

Void cxxxxdlg: onclose ()
{
// Todo: add your message handler code here and/or call default

 

Cdialog: oncancel (); // Add oncancel here

Cdialog: onclose ();
}

 

Because oncancle actually calls enddicel (idcancel), you can also follow the following changes:

 

 

Void cxxxxdlg: onclose ()
{
// Todo: add your message handler code here and/or call default

 

Enddicel (idcancel );

Cdialog: onclose ();
}

 

We know that the onclose function is the response function of the wm_close message, but why does it automatically call cxxxxdlg: oncancel () after the wm_close message is sent ()? I followed the code and roughly sorted out the process:

 

Wm_close

-> Enter void cxxxxdlg: onclose ()

-> Cdialog: onclose () 

->Void cxxxxdlg: onclose () returns

-> Void cxxxxdlg: oncancel ()

What is more amazing than counter is the cdialog: onclose () function:

This function does not know how to tell the system to call cxxxxdlg: onclose () after cxxxxdlg: oncancel () is returned. In debugging, assume that this function is staring away, it is not transferred to the cxxxxdlg: oncancel () function. In addition, the cxxxxdlg: oncancel () function is called after cxxxxdlg: onclose () is returned, assuming that the response uses a message, I think whether it should not be called after the return, the message should be processed immediately after being sent.

I have not obtained an answer for a long time on the Internet. I have recorded a temporary record here. Maybe I have made it clear one day, or I have been found to give a answer.