WinAPI: Rectangle - 绘制矩形

//声明:
Rectangle(
  DC: HDC;                {设备环境句柄}
  X1, Y1, X2, Y2: Integer {两个点的坐标}
): BOOL;


//举例:
procedure TForm1.FormPaint(Sender: TObject);
const
  x1 = 20;
  y1 = 20;
  x2 = 200;
  y2 = 100;
begin
  Rectangle(Canvas.Handle, x1,y1, x2,y2);
end;


//效果图:

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