Asp.Net s请求报传输流收到意外的 EOF 或 0 个字节

 WebClient client = new WebClient();
                try
                {
                    string res = "";
                  
                    System.Net.ServicePointManager.SecurityProtocol |= SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls | SecurityProtocolType.Ssl3;
                    if (IsHead)
                    {
                        client.Headers.Add("X-Requested-With", "XMLHttpRequest");
                    }
                    Stream stream = client.OpenRead(url);
                  
                    StreamReader sr = new StreamReader(stream, Encoding.UTF8);
                    res = sr.ReadToEnd();
                    sr.Close();
                    client.Dispose();
                    return res;
                }
                catch (Exception ex)
                {
                  
                    Log.Error(string.Format("请求url:{0},错误信息:{1}", url, ex.ToString()));
                    client.Dispose();
                    return "";
                }

　　在使用这段代码进行做爬虫请求数据的时候，报异常输流收到意外的 EOF 或 0 个字节 的异常。最后的解决方法参考了以下链接。

https://www.jianshu.com/p/5d2867435a6e