再学 GDI+[80]: 区域(9) - GetHRGN - 转为 GDI 的区域句柄

本例效果图:

---

代码文件:

---

unit Unit1;



interface



uses

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

  Dialogs, StdCtrls, ComCtrls;



type

  TForm1 = class(TForm)

    procedure FormPaint(Sender: TObject);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



uses GDIPOBJ, GDIPAPI;



procedure TForm1.FormPaint(Sender: TObject);

var

  g: TGPGraphics;

  b: TGPBrush;

  rgn: TGPRegion;

  RegionHandle: HRGN;

begin

  g := TGPGraphics.Create(Canvas.Handle);

  b := TGPHatchBrush.Create(HatchStyleDiagonalCross, aclSilver, aclLemonChiffon);

  rgn := TGPRegion.Create(MakeRect(40.0, 40, ClientWidth-80, ClientHeight-80));

  g.FillRegion(b, rgn);



  RegionHandle := rgn.GetHRGN(g);



  Canvas.Brush.Color := clRed;

  FrameRgn(Canvas.Handle, RegionHandle, Canvas.Brush.Handle, 2, 2);



  DeleteObject(RegionHandle);

  rgn.Free;

  b.Free;

  g.Free;

end;



end.


 
   

窗体文件:

---

object Form1: TForm1

  Left = 0

  Top = 0

  Caption = 'Form1'

  ClientHeight = 162

  ClientWidth = 197

  Color = clBtnFace

  Font.Charset = DEFAULT_CHARSET

  Font.Color = clWindowText

  Font.Height = -11

  Font.Name = 'Tahoma'

  Font.Style = []

  OldCreateOrder = False

  Position = poDesktopCenter

  OnPaint = FormPaint

  PixelsPerInch = 96

  TextHeight = 13

end