Автор: http://www.swissdelphicenter.ch

{ 
  With the ObjectBinaryToText Function you get a string 
  representation of an object 
  stored in a file or a stream. 

  Mit ObjectBinaryToText kann die Darstellung eines in einer Datei oder 
  einem Stream gespeicherten Objekts in eine verstandliche Textversion 
  konvertiert werden. 
}

 function ComponentToString(Component: TComponent): string;
 var
   BinStream: TMemoryStream;
   StrStream: TStringStream;
 begin
   BinStream := TMemoryStream.Create;
   try
     StrStream := TStringStream.Create(Result);
     try
       BinStream.WriteComponent(Component);
       BinStream.Seek(0, soFromBeginning);
       ObjectBinaryToText(BinStream, StrStream);
       StrStream.Seek(0, soFromBeginning);
       Result := StrStream.DataString;
     finally
       StrStream.Free;
     end;
   finally
     BinStream.Free
   end;
 end;

 procedure TForm1.Button2Click(Sender: TObject);
 begin
   ShowMessage(ComponentToString(Button1));
 end;