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[ASP.net教程]C# 在异步中使用HttpWebRequest出现的“正在终止线程”错误的解决方案


最近做接口对接,因需求变化需要用到异步推送信息,就利用委托做了异步。

程序运行过程中时不时出现“正在终止线程”的错误信息,导致两边订单信息不一致,代码如下:

       byte[] byteData = Encoding.UTF8.GetBytes(parameters);      HttpWebResponse response=null;      Stream myResponseStream = null;      Stream myRequestStream = null;try      {        var request=(HttpWebRequest) WebRequest.Create(Url);        request.Proxy = null;//不使用代理        request.Method = "POST";        request.ContentType = "application/x-www-form-urlencoded";        request.ContentLength = byteData.Length;                using (myRequestStream = request.GetRequestStream())        {          myRequestStream.Write(byteData, 0, byteData.Length);        }        response = (HttpWebResponse) request.GetResponse();        myResponseStream = response.GetResponseStream();        //将响应流转成        new if (myResponseStream != null)          doc.Load(myResponseStream);        //返回        return doc;      }      catch (Exception ex)      {        LogHelper.CreateLog("post信息时出错!信息:" + ex.Message, orderid, httpContext);        return null;      }      finally      {        if (myResponseStream != null)        {          myResponseStream.Close();          myResponseStream.Dispose();        }        if (response != null)        {          response.Close();          response.Dispose();        }        if (myRequestStream != null)        {          myRequestStream.Close();          myRequestStream.Dispose();        }      }

网上寻找解决方案,基本上都是Response.Redirect导致的错误。我的代码上面并没有这些玩意儿。。。

实在是无法组织语言了,归根到底的原因就是C#中使用多线程使用HttpWebRequest时,默认的连接数只有2。

然后有时候因为对方服务器的原因导致访问超时,如果没有做超时处理的话,request对象就不会被释放,后面便导致一系列的问题。

解决方法之一就是在调用HttpWebRequest对象之前将连接数改大。

System.Net.ServicePointManager.DefaultConnectionLimit = 24

 

解决后代码:

      byte[] byteData = Encoding.UTF8.GetBytes(parameters);      HttpWebResponse response=null;      Stream myResponseStream = null;      Stream myRequestStream = null;      System.Net.ServicePointManager.DefaultConnectionLimit = 24;      try      {        var request=(HttpWebRequest) WebRequest.Create(Url);        request.Proxy = null;//不使用代理        request.KeepAlive = false;//不建立持久性连接        request.Method = "POST";        request.ContentType = "application/x-www-form-urlencoded";        request.ContentLength = byteData.Length;                using (myRequestStream = request.GetRequestStream())        {          myRequestStream.Write(byteData, 0, byteData.Length);        }        response = (HttpWebResponse) request.GetResponse();        myResponseStream = response.GetResponseStream();        //将响应流转成        new if (myResponseStream != null)          doc.Load(myResponseStream);        //返回        return doc;      }      catch (Exception ex)      {        LogHelper.CreateLog("post信息时出错!信息:" + ex.Message, orderid, httpContext);        return null;      }      finally      {        if (myResponseStream != null)        {          myResponseStream.Close();          myResponseStream.Dispose();        }        if (response != null)        {          response.Close();          response.Dispose();        }        if (myRequestStream != null)        {          myRequestStream.Close();          myRequestStream.Dispose();        }      }      

 

这个个数,有相关说法是CPU的数量*2,具体有待考证,不过已经解决了我的问题。

其他解决方式参考连接:

http://www.cnblogs.com/eaglet/archive/2012/05/18/2507179.html

http://www.cnblogs.com/1971ruru/archive/2012/04/11/2442589.html

http://blog.sina.com.cn/s/blog_3eea4f680100s48d.html