C#使用WebClient的代理

这是我现在掌握的密码

using (WebClient client = new WebClient()) 
{
    Console.WriteLine(client.DownloadString("http://bot.whatismyipaddress.com/"));
}

现在，我想为代理添加两个选项

标准IP:Proxy的一个选项

带有身份验证的选项

我似乎不知道如何将它与上面的代码连接起来

    using (WebClient client = new WebClient()) {
        client.Proxy = new WebProxy("31.4.5.26", 8080); // proxy's host,port
        client.Proxy.Credentials = new NetworkCredential("proxyuser", "proxypassword");
        Console.WriteLine(client.DownloadString("http://bot.whatismyipaddress.com/"));
    }

对我来说很好