Mega Code Archive

Detecting simultaneous left and right mouse clicks

Title: Detecting simultaneous left and right mouse clicks Question: How to known if the user has pressed simultaneously the left and right mouse buttons? Answer: The OnMouse event is declared as follows: procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer); If you find in the Classes unit the declaration of TShiftState is: TShiftState = set of (ssShift, ssAlt, ssCtrl, ssLeft, ssRight, ssMiddle, ssDouble); So you need to test if sLeft and ssRight are present in the Shift parameter, now your code must be like this: procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer); begin if (ssRight in Shift) and (ssLeft in Shift) then ShowMessage('The user has pressed Left and Right buttons') ; end; //MWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWM