WebProxy error: Proxy Authentication Required

问题

I use the following code to obtaing html data from the internet:

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");

But the following error is appeared: "Proxy Authentication Required". I can't use default proxy because of my code runs from windows service under the special account which there is no default proxy settings for. So, I want to specidy all proxy settings in my code. Please advice me how to resolve this error.

回答1:

You've to set the WebClient.Proxy Property..

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");

回答2:

This worked for me:

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

回答3:

Try this code

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();

来源：https://stackoverflow.com/questions/13008964/webproxy-error-proxy-authentication-required

标签

.net

webclient

networkcredentials

webproxy