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...draw a bounding box with the mouse?
Autor: Borland Delphi How
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Tip Rating (15):  
     




private
  
{ Private declarations }
  
AnchorX, AnchorY,
  CurX, CurY: Integer;
  Bounding: Boolean;
end;

implementation

procedure 
TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  
AnchorX := X;
  CurX := X;
  AnchorY  := Y; 
  CurY := Y;
  Bounding := True;
end;

procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
  if 
Bounding then 
  begin
    
Canvas.Pen.Mode := pmNot;
    Canvas.Pen.Width := 2;
    Canvas.Brush.Style := bsClear;
    Canvas.Rectangle(AnchorX, AnchorY, CurX, CurY);
    CurX := X; 
    CurY := Y;
    Canvas.Rectangle(AnchorX, AnchorY, CurX, CurY);
  end;
end;

procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  if 
Bounding then 
  begin
    
Bounding := False;
    Canvas.Pen.Mode := pmNot;
    Canvas.Brush.Style := bsClear;
    Canvas.Rectangle(AnchorX, AnchorY, CurX, CurY);
  end;
end;

 

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