再學GDI+[26]: TGPPen - 畫筆對齊 - SetAlignment

本例效果圖:

代碼文件:unit Unit1;
interface
uses
　Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
　Dialogs, StdCtrls, ExtCtrls;
type
　TForm1 = class(TForm)
　　RadioGroup1: TRadioGroup;
　　procedure FormPaint(Sender: TObject);
　　procedure FormCreate(Sender: TObject);
　　procedure RadioGroup1Click(Sender: TObject);
　end;
var
　Form1: TForm1;
implementation
{$R *.dfm}
uses GDIPOBJ, GDIPAPI;
procedure TForm1.FormCreate(Sender: TObject);
begin
　with RadioGroup1 do
　begin
　　Align := alBottom;
　　Items.Add('PenAlignmentCenter');
　　Items.Add('PenAlignmentInset');
　　Columns := 2;
　　ItemIndex := 0;
　end;
end;
procedure TForm1.FormPaint(Sender: TObject);
var
　g: TGPGraphics;
　p: TGPPen;
　rect: TRect;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　g.Clear($FFFFFFFF);
　p := TGPPen.Create($FFEE82EE, 20);
　rect := ClientRect;
　InflateRect(rect, -50, -50);
　OffsetRect(rect, 0, -20);
　p.SetAlignment(TPenAlignment(RadioGroup1.ItemIndex));
　g.DrawRectangle(p, MakeRect(rect));
　p.SetColor($FF000000);
　p.SetWidth(1.5);
　g.DrawRectangle(p, MakeRect(rect));
　p.Free;
　g.Free;
end;
procedure TForm1.RadioGroup1Click(Sender: TObject);
begin
　Repaint;
end;
end.