WebProxy错误:需要代理身份验证

Question

我使用以下代码从互联网获取html数据：

WebProxy p = new WebProxy("localproxyIP:8080", true);
p.Credentials = new NetworkCredential("domain\\user", "password");
WebRequest.DefaultWebProxy = p;
WebClient client = new WebClient();
string downloadString = client.DownloadString("http://www.google.com");

但出现以下错误："Proxy Authentication Required“。我不能使用默认代理，因为我的代码运行在windows服务的特殊帐户下，没有默认的代理设置。所以，我想在我的代码中指定所有的代理设置。请建议我如何解决这个错误。

Answer 1

您必须设置WebClient.Proxy属性..

WebProxy p = new WebProxy("localproxyIP:8080", true);
p.Credentials = new NetworkCredential("domain\\user", "password");
WebRequest.DefaultWebProxy = p;
WebClient client = new WebClient();
**client.Proxy = p;**
string downloadString = client.DownloadString("http://www.google.com");

Answer 2

这对我很有效：

IWebProxy defaultWebProxy = WebRequest.DefaultWebProxy;
defaultWebProxy.Credentials = CredentialCache.DefaultCredentials;
client = new WebClient
    {
        Proxy = defaultWebProxy
    };
string downloadString = client.DownloadString(...);

Answer 3

试试这段代码

var transferProxy = new WebProxy("localproxyIP:8080", true);
transferProxy.Credentials = new NetworkCredential("user", "password", "domain");
var transferRequest = WebRequest.Create("http://www.google.com");
transferRequest.Proxy = transferProxy;
HttpWebResponse transferResponse = 
    (HttpWebResponse)transferRequest.GetResponse(); 
System.IO.Stream outputStream = transferResponse.GetResponseStream();