最近微信公众号功能莫名其妙的出问题，在调腾讯和百度接口就出问题，也不知道哪里抽风，只要调用外部接口，POST或者GET提交，准备出错。提示基础连接已关闭......
httpWebRequest请求错误,基础连接已经关闭: 连接被意外关闭
研究很久很久，搞不明白，不是一向都好好的嘛，难道只能网络也只需要赞美吗？代码都没动啊，以前跑得也很正常的啊，突然之间就提示基础连接已关闭，什么什么错误之类，搞了N久，都不知道为什么？蛋都痛得不行了。
以前的代码
public static string HttpGetWebResponse(string url){string m = string.Empty;Stream stream = null;StreamReader sr = null;try{WebRequest request = WebRequest.Create(url);WebResponse response = request.GetResponse();stream = response.GetResponseStream();sr = new StreamReader(stream, System.Text.Encoding.UTF8);m = sr.ReadToEnd();return m;}catch (Exception e){LogHelper.WriteLog(e.Message);return string.Empty;}finally{if (stream != null){stream.Close();}if (sr != null){sr.Close();}}}
这个有什么问题啊？有什么问题啊？有什么问题啊？不重要的事情也说三遍
不知道为什么，就是过不去。无奈之下，百般百度之下
public static string GetPage(string posturl){Stream instream = null;StreamReader sr = null;try{HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(posturl);request.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;)";request.KeepAlive = false;ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls;ServicePointManager.DefaultConnectionLimit = 200;request.ServicePoint.ConnectionLimit = 200;request.ContentType = "application/x-www-form-urlencoded";request.ProtocolVersion = HttpVersion.Version10;request.Timeout = 5 * 1000;request.Method = "GET";//发送请求并获取相应回应数据HttpWebResponse response = request.GetResponse() as HttpWebResponse;//直到request.GetResponse()程序才开始向目标网页发送Post请求instream = response.GetResponseStream();sr = new StreamReader(instream, Encoding.UTF8);//返回结果网页（html）代码return sr.ReadToEnd();}catch (Exception ex){LogHelper.WriteLog("GET" + posturl + ex.Message);return string.Empty;}finally {if (sr != null) {sr.Close();sr = null;}if (instream != null) {instream.Dispose();instream.Close();instream = null;}}}
发现这么写就可以了，关键代码好像就一句
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls;
但是，但是，但是这样只是表示连腾讯的接口是可以，连百度的接口却不行的。我们系统是先测试的百度接口，百度搞好，连腾讯接口总是不行。着急，上火都没鸟用。
百度写如下：
public static string HttpPost(string Url, string postDataStr){try{System.GC.Collect();HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);request.Method = "POST";request.ContentType = "application/x-www-form-urlencoded";request.ContentLength = Encoding.UTF8.GetByteCount(postDataStr);request.ProtocolVersion = HttpVersion.Version10;//ServicePointManager.ServerCertificateValidationCallback = new RecommendService( RemoteCertificateValidationCallback(CheckValidationResult);ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3;Stream myRequestStream = request.GetRequestStream();StreamWriter myStreamWriter = new StreamWriter(myRequestStream, Encoding.GetEncoding("gb2312"));myStreamWriter.Write(postDataStr);myStreamWriter.Close();HttpWebResponse response = (HttpWebResponse)request.GetResponse();//response.Cookies = cookie.GetCookies(response.ResponseUri);Stream myResponseStream = response.GetResponseStream();StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));string retString = myStreamReader.ReadToEnd();myStreamReader.Close();myResponseStream.Close();return retString;}catch (Exception e) {LogHelper.WriteLog("post提交失败" +Url + e.Message);return "";}}
ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3;
关键代码好像就这一句
到这里似乎可以总结了，就是两个接口的安全协议不一样。
这里有两个疑问，为什么会不一样了，为什么以前就是好的了。
运行环境IIS 下 framework2.0 语言C#，网上也说如果在4.0下就不需要如此复杂。因为服务器比较老，一时半会又没有银子升级，正好解释一下什么是没钱的人命苦。
最后了，似乎还是有点知其然不知其所以然。
如果觉得《基础连接已关闭解决办法》对你有帮助，请点赞、收藏，并留下你的观点哦！
