Disable the select and copy to clipboard capabilities in a TMemo (Views: 28)
Problem/Question/Abstract: How to disable the select and copy to clipboard capabilities in a TMemo Answer: Solve 1: Use OnKeyDown and OnKeyPress handlers for the memo to catch the shortcuts for copy and cut and set key := 0 for them. Provide a handler for the OnContextMenu event in which you set Handled to true to prevent the default popup menu from coming up. That should do it. procedure TForm1.Memo1KeyDown(Sender: TObject; var Key: Word; Shift: TShiftState); begin if ssCtrl in Shift then case Key of Ord('C'), Ord('X'), VK_INSERT: Key := 0; end else if (ssShift in Shift) and (Key = VK_DELETE) then Key := 0; end; procedure TForm1.Memo1ContextPopup(Sender: TObject; MousePos: TPoint; var Handled: Boolean); begin Handled := true; end; procedure TForm1.Memo1KeyPress(Sender: TObject; var Key: Char); begin if Key in [^C, ^X] then Key := #0; end; Solve 2: The easiest way would be to set the Enabled property of the Memo (or Edit) control to False so that the control cannot receive events. This drawback to this method is the user won't be able to scroll the text and the disabled text looks bad. In order to prevent the user from writing in the memo, we set its ReadOnly property to True. To prevent the user from selecting text with the mouse, we generate the handler of the MouseMove event of the control and write the following code: procedure TForm1.Memo1MouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer); begin if ssLeft in Shift then Memo1.SelLength := 0; end; In order to prevent the user from performing a selection using the keyboard, we generate the handlers of the KeyDown and KeyUp events, assigning the OnKeyDown and OnKeyUp properties to the same procedure: procedure TForm1.Memo1KeyDownUp(Sender: TObject; var Key: Word; Shift: TShiftState); begin if (ssShift in Shift) and (Key in [VK_LEFT, VK_RIGHT, VK_UP, VK_DOWN, VK_PRIOR, VK_NEXT, VK_HOME, VK_END]) then Key := 0; end; |