如何根据字符串创建类的实例？

[hexenzhou]

假设
str1 := 'TObject1';
str2 := 'TObject2';
....
....
如何根据类名来创建类的实例，比如CreateObject就可以根据类名来创建类实例，不过它创建的是Com对象，我不需要Com对象，我需要是普通的Delphi类，望各位高手赐教！

[firstshine]

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;

type
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
ff:String;

constructor Create(AOwner: TComponent); override;
end;

TForm1Class = Class of TForm1;

var
Form1: TForm1;

implementation

{$R *.dfm}

{ TForm1 }

constructor TForm1.Create(AOwner: TComponent);
begin
inherited Create(AOwner);

FF:='Test';
end;

procedure TForm1.Button1Click(Sender: TObject);
var
a:TForm1Class;
b:TForm1;
begin
a:=TForm1Class(GetClass('TForm1'));
if a=nil then exit;

b:=a.Create(nil);
showmessage(b.ff);
end;

Initialization
RegisterClass(TForm1);

end.

[hexenzhou]

unit Unit1;

interface

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

type
TTestClass = class of TTest;
TTest = class(TPersistent)
public
function GetName: string;
end;


TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
RegisterClass(TTest);
Caption := TTest(FindClass('TTest').Create).getName;
end;

{ TTest }

function TTest.GetName: string;
begin
Result := 'hdhhd';
end;

end.

firstshine(黑里透红)和我的方法一样，嘿嘿！结贴！