在通过
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url); req.Method = "GET"; HttpWebResponse sp = (HttpWebResponse)req.GetResponse();作处理时，有些输入有些URL会在HttpWebResponse sp = (HttpWebResponse)req.GetResponse();的时候抛出一个“基础连接已经关闭: 未能为 SSL/TLS 安全通道建立信任关系”的异常。 最简单的办法是: 1,先加入命名空间：
using System.Net.Security;using System.Security.Authentication;using System.Security.Cryptography.X509Certificates;2，再重载CheckValidationResult方法，返回true
public bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors) { // 总是接受 return true; }3,然后在
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url);前面加上如下一行代码：
ServicePointManager.ServerCertificatidationCallback = new System.Net.Security.RemoteCertificatidationCallback(CheckValidationResult);//验证服务器证书回调自动验证新闻热点
疑难解答
