本例效果圖:
代碼文件:unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1 = class(TForm)
ListBox1: TListBox;
procedure FormCreate(Sender: TObject);
procedure FormPaint(Sender: TObject);
procedure ListBox1Click(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
uses GDIPOBJ, GDIPAPI;
procedure TForm1.FormCreate(Sender: TObject);
begin
ListBox1.Align := alRight;
with ListBox1.Items do
begin
Add('SmoothingModeInvalid ');
Add('SmoothingModeDefault ');
Add('SmoothingModeHighSpeed ');
Add('SmoothingModeHighQuality');
Add('SmoothingModeNone ');
Add('SmoothingModeAntiAlias ');
end;
end;
procedure TForm1.FormPaint(Sender: TObject);
var
g: TGPGraphics;
p: TGPPen;
begin
g := TGPGraphics.Create(Canvas.Handle);
p := TGPPen.Create(aclRed, 2);
g.SetSmoothingMode(ListBox1.ItemIndex - 1);
g.DrawEllipse(p, 10, 10, ClientWidth - ListBox1.Width - 20, ClientHeight - 20);
g.DrawLine(p, 0, 0, ClientWidth - ListBox1.Width, ClientHeight);
g.DrawLine(p, ClientWidth - ListBox1.Width, 0, 0, ClientHeight);
p.Free;
g.Free;
end;
procedure TForm1.ListBox1Click(Sender: TObject);
begin
Repaint;
end;
end.
