本例效果图:
![](https://www.cnblogs.com/images/cnblogs_com/del/134145/o_85223.gif)
![](https://www.cnblogs.com/images/cnblogs_com/del/134145/o_85223.gif)
unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm1 = class(TForm) Button1: TButton; Button2: TButton; Button3: TButton; Button4: TButton; Button5: TButton; procedure Draw; procedure FormCreate(Sender: TObject); procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure Button4Click(Sender: TObject); procedure Button5Click(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} var R: TRect; procedure TForm1.Draw; begin Refresh; Canvas.FillRect(R); end; procedure TForm1.FormCreate(Sender: TObject); begin Button1.Caption := '绘制矩形'; Button2.Caption := '上移'; Button3.Caption := '下移'; Button4.Caption := '左移'; Button5.Caption := '右移'; end; procedure TForm1.Button1Click(Sender: TObject); begin R := Bounds(80, 60, 60, 60); Randomize; Canvas.Brush.Color := Random($FFFFFF); Draw; end; procedure TForm1.Button2Click(Sender: TObject); begin OffsetRect(R, 0, -10); Draw; end; procedure TForm1.Button3Click(Sender: TObject); begin OffsetRect(R, 0, 10); Draw; end; procedure TForm1.Button4Click(Sender: TObject); begin OffsetRect(R, -10, 0); Draw; end; procedure TForm1.Button5Click(Sender: TObject); begin OffsetRect(R, 10, 0); Draw; end; end.