Delphi 假如有一张bmp图片，如何按指定大小将它画在窗体上？

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms;

type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormPaint(Sender: TObject);
private
FBmp:TBitmap;
public
end;
var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
FBmp:=TBitmap.Create;
FBmp.LoadFromFile('D:\01.bmp');
FBmp.Transparent := True;
end;

procedure TForm1.FormPaint(Sender: TObject);
Var
R:TRect;
begin
R.Left := 100;
R.Top := 100;
R.Right := R.Left + 333;
R.Bottom := R.Top + 333;
Canvas.StretchDraw(R,FBmp);
end;

end.