ossnet 实现URL授权文件上传

正在对接一个支付渠道,这边采用oss上传附件方式,通过请求他们的接口返回了一个授权链接:如下:



http://****.pay200.cn/A10000002/20171011/C008001710111525008623/j8mpjw7nlS9Yb.rar?Expires=1507706611&OSSAccessKeyId=*******************&Signature=zpHT9reBoi/POrti2FFWdZGQzUM=&pay200_fileRootPath=A10000002/20171011/C008001710111525008623/j8mpjw7nlS9Yb.rar&pay200_rootHost=temp.pay200.cn


看了官方说明得到签名url之后直接带入

                var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
                PutObjectResult putResult = null;
                try
                {
                    //ObjectMetadata metaData = new ObjectMetadata();
                    //metaData.UserMetadata.Add("myfield","test");
                    putResult = client.PutObject(signedUrl, fileToUpload);
                    result = "上传成功";
                }
                catch (Exception ex)
                {
                    putResult = null;
                    result = ex.Message;
                    //throw;
                }


但是我发起上传请求之后总是返回我服务器拒绝 403错误,请问下是什么原因。