WinAPI: RoundRect - 绘制圆角矩形

//声明:
RoundRect(
  DC: HDC;                        {设备环境句柄}
  X1, Y1, X2, Y2, X3, Y3: Integer {点1、点2是构成矩形的坐标; X3是圆角宽度、Y3是圆角高度}
): BOOL;


//举例:
procedure TForm1.FormPaint(Sender: TObject);
const
  x1 = 20;
  y1 = 20;
  x2 = 200;
  y2 = 100;
  x3 = 30;
  y3 = 30;
begin
  RoundRect(Canvas.Handle, x1,y1, x2,y2, x3,y3);
end;


//效果图:

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