没有权限 设置权限

WebClient client=new WebClient();

//NetworkCredential credentials = new NetworkCredential("名字", "密码");

//client.Credentials = credentials;

 

未能为 SSL/TLS 安全通道建立信任的解决办法 

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

//ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);