问TStream到TStringList的unicode失败

EN

program Project1;

{$APPTYPE CONSOLE}
{$R *.res}

uses
  Classes, SysUtils;

// http://stackoverflow.com/questions/732666
// Converting TMemoryStream to String in Delphi 2009
function MemoryStreamToString(M: TMemoryStream): string;
begin
  SetString(Result, PChar(M.Memory), M.Size div SizeOf(Char));
end;

procedure Test1;
var
  SrcList: TStrings;
  S: String;
  AStream: TStream;
begin
  SrcList := TStringList.Create;
  try
    with SrcList do
    begin
      Add('aa');
      Add('bb');
      Add('cc');
    end;

    S := SrcList.Text;

    AStream := TMemoryStream.Create;
    try
      // AStream.Write(S[1], Length(S));
      // AStream.Write(S[1], Length(S) * SizeOf(Char));
      AStream.Write(Pointer(S)^, Length(S) * SizeOf(Char));

      WriteLn(MemoryStreamToString(TMemoryStream(AStream)));
    finally
      AStream.Free;
    end;
  finally
    SrcList.Free;
  end;
end;

procedure Test2;
var
  SrcList: TStrings;
  S: String;
  AStream: TStream;
  DestList: TStringList;
  I: Integer;
begin
  SrcList := TStringList.Create;
  try
    with SrcList do
    begin
      Add('aa');
      Add('bb');
      Add('cc');
    end;

    S := SrcList.Text;

    AStream := TMemoryStream.Create;
    try
      // AStream.Write(S[1], Length(S));
      // AStream.Write(S[1], Length(S) * SizeOf(Char));
      AStream.Write(Pointer(S)^, Length(S) * SizeOf(Char));

      DestList := TStringList.Create;
      try
        AStream.Position := 0;
        DestList.LoadFromStream(AStream);

        WriteLn(DestList.Text);
      finally
        DestList.Free;
      end;
    finally
      AStream.Free;
    end;
  finally
    SrcList.Free;
  end;
end;

begin
  try
    Test1;
    Test2;
  except
    on E: Exception do
      WriteLn(E.ClassName, ': ', E.Message);
  end;
  Readln;
end.