远程服务器返回错误：（401）当我尝试通过Web客户端下载文件时发生未授权错误

Question

我在Windows窗体应用程序中运行以下代码：

WebClient client = new WebClient();
WebProxy wp = new WebProxy("http://50.35.125.91:81/");
client.UseDefaultCredentials = true;
wp.Credentials = CredentialCache.DefaultCredentials;
wp.Credentials = new NetworkCredential("matif", "yyy", "xyz");


client.Proxy = wp;
client.DownloadFile("http://50.35.125.91:81/abc/AppUpdate.xml", @"D:\abc.xml");

每次都会出现以下异常

远程服务器返回错误：（401）未经授权。

我确信凭据有效，

Answer 1

为代理和客户提供凭据：

using (WebClient client = new WebClient())
{
    WebProxy wp = new WebProxy("http://50.35.125.91:81/");
    wp.Credentials = new NetworkCredential("matif", "yyy", "xyz");

    client.UseDefaultCredentials = false;
    client.Credentials = wp.Credentials;
    client.Proxy = wp;
    client.DownloadFile("http://50.35.125.91:81/abc/AppUpdate.xml", @"D:\abc.xml");
}

Answer 2

您正在使用默认凭据。 UseDefaultCredentials应设置为false而不是true：

client.UseDefaultCredentials = false; 

这条线你根本不需要：

wp.Credentials = CredentialCache.DefaultCredentials;

Answer 3

试试这个：

using (var Client = new WebClient())
{            
   Client.Credentials = new NetworkCredential("matif", "yyy", "xyz");
   Client.DownloadFile("http://50.35.125.91:81/abc/AppUpdate.xml", @"D:\abc.xml");
}