再学GDI+[27]: TGPPen

本例效果图:

代码文件:unit Unit1;
interface
uses
　Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
　Dialogs, StdCtrls, ExtCtrls;
type
　TForm1 = class(TForm)
　　ComboBox1: TComboBox;
　　procedure FormCreate(Sender: TObject);
　　procedure FormPaint(Sender: TObject);
　　procedure ComboBox1Change(Sender: TObject);
　end;
var
　Form1: TForm1;
implementation
{$R *.dfm}
uses GDIPOBJ, GDIPAPI, TypInfo;
procedure TForm1.FormCreate(Sender: TObject);
var
　i: Integer;
begin
　for i := 0 to 5 do
　　ComboBox1.Items.Add(GetEnumName(TypeInfo(TDashStyle), i));
　ComboBox1.ItemIndex := 0;
end;
procedure TForm1.FormPaint(Sender: TObject);
var
　g: TGPGraphics;
　p: TGPPen;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　g.Clear($FFFFFFFF);
　p := TGPPen.Create(aclLimeGreen, 10);
　p.SetDashStyle(TDashStyle(ComboBox1.ItemIndex));
　g.DrawLine(p, 0, 0, ClientWidth, ClientHeight);
　p.Free;
　g.Free;
end;
procedure TForm1.ComboBox1Change(Sender: TObject);
begin
　Repaint;
end;
end.