Restrict the mouse movement to form

Problem/Question/Abstract:

Using the Windows API function ClipCursor, it is possible to restrict the movement of the mouse to a specific rectangular region on the screen.

Answer:

//restrict the mouse mouvement to form and release
//this restriction after a click on the form

procedure TForm1.FormCreate(Sender: TObject);
var
  r: TRect;
begin
  //it would be good idea to move the
  //mouse inside the form before restriction
  r := BoundsRect;
  ClipCursor(@R);
end;

procedure TForm1.FormClick(Sender: TObject);
begin
  //always be sure to release the cursor
  ClipCursor(nil);
end;