本文整理自网络，侵删。
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, ComCtrls, Buttons, StdCtrls, ExtCtrls;
type
TForm1 = class(TForm)
Panel1: TPanel;
Label1: TLabel;
Label2: TLabel;
Edit1: TEdit;
SpeedButton1: TSpeedButton;
SpeedButton2: TSpeedButton;
SpeedButton3: TSpeedButton;
SpeedButton4: TSpeedButton;
UpDown1: TUpDown;
procedure SpeedButton1Click(Sender: TObject);
procedure SpeedButton2Click(Sender: TObject);
procedure SpeedButton3Click(Sender: TObject);
procedure SpeedButton4Click(Sender: TObject);
procedure Edit1Change(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure FormMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
procedure FormMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
private
{ Private declarations }
jyX,jyY:integer;
blht:boolean;
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.SpeedButton1Click(Sender: TObject);
begin
canvas.Pen.color:=clred;
end;
procedure TForm1.SpeedButton2Click(Sender: TObject);
begin
canvas.Pen.color:=clgreen;
end;
procedure TForm1.SpeedButton3Click(Sender: TObject);
begin
canvas.Pen.Color:=clblue;
end;
procedure TForm1.SpeedButton4Click(Sender: TObject);
begin
close;
end;
procedure TForm1.Edit1Change(Sender: TObject);
begin
canvas.Pen.Width:=strtoint(edit1.Text);
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
blht:=false;
speedbutton1.Down:=true;
canvas.Pen.Color:=clred;
end;
procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
jyX:=x;
jyY:=y;
blht:=true;
end;
procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
begin
if blht then
begin
canvas.MoveTo(jyX,jyY);
canvas.LineTo(x,y);
jyX:=x;
jyY:=y;
end;
end;
procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
blht:= not blht;
end;
end. 相关阅读 >>
Delphi colorbox不需要系统那么多颜色，只想自定义显示其中几个，怎么做？
Delphi 如何从一张图片中裁剪一部分距形图片另存为文件（使用canvas.copyrect）
Delphi controls 属性与继承 tshape 类的小练习
更多相关阅读请进入《Delphi》频道 >>
