Delphi图象截取编程示例(7)

(七)抓取窗体或控件图片窗体

创建一个新的Form2，保存为Capture2.pas。设置属性BorderIcons的四个属性为false.

BorderStyle设为bsNone,FormStyle设为fsStayOnTop.

两个公共变量:fRect:TRect,fBmp:TBitmap;

unit Capture2;

interface

uses

Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

Dialogs;

type

TForm2 = class(TForm)

procedure FormCreate(Sender: TObject);

procedure FormActivate(Sender: TObject);

procedure FormDestroy(Sender: TObject);

procedure FormPaint(Sender: TObject);

procedure FormMouseUp(Sender: TObject; Button: TMouseButton;

Shift: TShiftState; X, Y: Integer);

private

{ Private declarations }

public

fRect:TRect;

fBmp:TBitmap;

end;

var

Form2: TForm2;

implementation

{$R *.dfm}

//创建一个新的自定义光标CURSOR_1,放在Capture2.res资源

//文件中.是32*32的白色矩形边框，用来指示抓图的范围.

procedure TForm2.FormCreate(Sender: TObject);

var aDC:HDC;

const crHand = -18;

begin

Screen.Cursors[crHand]:=LoadCursor(hInstance,'CURSOR_1');

Cursor:=crHand;

fBmp:= TBitmap.Create ;

fBmp.Width := Screen.Width ;

fBmp.Height:= Screen.Height ;

aDC := GetDC(0);

BitBlt(fBmp.Canvas.Handle,0,0,Screen.Width,Screen.Height,aDC,0,0,srcCopy);

ReleaseDC(0,aDC);

SetBounds(0,0,Screen.Width,Screen.Height);

end;

procedure TForm2.FormActivate(Sender: TObject);

const crHand=-18;

begin

Screen.Cursors[crHand]:=LoadCursor(hInstance,pChar('CURSOR_1'));

Cursor:=crHand;

end;

procedure TForm2.FormDestroy(Sender: TObject);

begin

fBmp.Free;

Screen.Cursor := crDefault;

end;

procedure TForm2.FormPaint(Sender: TObject);

begin

Canvas.Draw(0,0,fBmp);

end;

procedure TForm2.FormMouseUp(Sender: TObject; Button: TMouseButton;

Shift: TShiftState; X, Y: Integer);

begin

ModalResult:=mrOK;

end;

end.