在从亚马逊S3检索对象后，如何从流中获取常规的Delphi字符串？

uses
  ..., REST.Client, System.Classes;

function GetS3ObjectAsString(AWSAccessKey, AWSSecretKey, BucketName, ObjectKey: string): string;
var
  S3Client: TRESTClient;
  S3Request: TRESTRequest;
  S3Response: TRESTResponse;
  ObjectStream: TMemoryStream;
  ObjectStringStream: TStringStream;
begin
  // 创建S3客户端
  S3Client := TRESTClient.Create('https://s3.amazonaws.com');
  S3Client.AccessToken := AWSAccessKey;
  S3Client.Secret := AWSSecretKey;

  // 创建S3请求
  S3Request := TRESTRequest.Create(nil);
  S3Request.Client := S3Client;
  S3Request.Method := rmGET;
  S3Request.Resource := BucketName + '/' + ObjectKey;

  // 创建S3响应
  S3Response := TRESTResponse.Create(nil);
  S3Request.Response := S3Response;

  try
    // 发送S3请求
    S3Request.Execute;

    // 从流中获取Delphi字符串
    ObjectStream := TMemoryStream.Create;
    ObjectStringStream := TStringStream.Create('', TEncoding.UTF8);
    try
      ObjectStream.LoadFromStream(S3Response.RawBytes);
      ObjectStream.Position := 0;
      ObjectStringStream.LoadFromStream(ObjectStream);
      Result := ObjectStringStream.DataString;
    finally
      ObjectStream.Free;
      ObjectStringStream.Free;
    end;
  finally
    S3Client.Free;
    S3Request.Free;
    S3Response.Free;
  end;
end;