int DoModal( HWND hWndParent = ::GetActiveWindow() );
Return Value
If successful, the return value is the resource ID of the control that dismissed the dialog box.
If the function fails, the return value is –1. To get extended error information, call GetLastError.
Parameters
hWndParent
A handle to the parent of the dialog box. If no value is provided, the parent is set to the current active window.
Remarks
Invokes a modal dialog box and returns the dialog-box result when done. This method handles all interaction with the user while the dialog box is active. This is what makes the dialog box modal; that is, the user cannot interact with other windows until the dialog box is closed.