using System;

namespace TestDynamicIp
{

    class Program
    {

        static string order = "这里需要改为您自己的IP提取码";
        static bool run = true;
        static string ipApi = "http://api.ip.data5u.com/dynamic/get.html?order=" + order;
        static string targetUrl = "http://pv.sohu.com/cityjson?ie=utf-8";

        public static void Main(string[] args)
        {
            // 抓取HTTPS网址时，需要接受证书，否则会报错：基础链接已经关闭,未能为SSL/TLS 安全通道建立信任关系
            System.Net.ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback((object sender, System.Security.Cryptography.X509Certificates.X509Certificate certificate, System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors errors) =>
            {
                return true; //总是接受证书  
            });
            System.Net.ServicePointManager.SecurityProtocol = System.Net.SecurityProtocolType.Ssl3 | System.Net.SecurityProtocolType.Tls;

            Console.WriteLine("\n********************\nC#测试爬虫（动态）代理IP\n********************\n");
            Console.WriteLine("请求网址为：" + targetUrl);
            StartCrawl();
            Console.WriteLine("\n********************\n测试结束，按任意键退出程序\n********************\n");
            Console.ReadKey(true);
        }

        public static void StartCrawl()
        {
            for (int i = 0; i < 10; i++)
            {
                Console.WriteLine("\n>>>>>>>>>>>>>>>>>>>>>>>第" + i + "次请求测试");
                // 获取动态IP				
                Uri uri = new Uri(ipApi);
                System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(ipApi);
                // 设置超时时间为20秒
                request.Timeout = 20000;
                System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)request.GetResponse();
                System.IO.Stream stream = response.GetResponseStream();
                System.IO.StreamReader reader = new System.IO.StreamReader(stream);
                String iptxt = reader.ReadToEnd();
                reader.Dispose();
                reader.Close();
                string[] ipports = iptxt.Split(new String[] { "\n" }, StringSplitOptions.None);
                System.Threading.Thread.Sleep(1000);
                try
                {
                    // 定义client
                    string ipport = ipports[(int)(ipports.Length * new Random().Next(0, 1))];
                    System.Net.WebClient client = new System.Net.WebClient();
                    client.Encoding = System.Text.Encoding.GetEncoding("GB2312");
                    // 设置代理
                    System.Net.WebProxy proxy = new System.Net.WebProxy();
                    proxy.Address = new Uri("http://" + ipports[0] + "/");
                    client.Proxy = proxy;
                    // 获取网页内容
                    byte[] byResponse = client.DownloadData(targetUrl);
                    String txt = System.Text.Encoding.GetEncoding("GB2312").GetString(byResponse);
                    Console.WriteLine("使用代理" + ipports[0] + "得到如下内容：\n" + txt);
                    client.Dispose();
                }
                catch (Exception e) {
                    Console.WriteLine("出错了：" + e.Message);
                }
            }
        }
    }
}

HttpWebRequest httpRequest = (HttpWebRequest)HttpWebRequest.Create("http://www.baidu.com");
httpRequest.Method = "GET";
httpRequest.Credentials = CredentialCache.DefaultCredentials;

// 设置代理属性WebProxy
WebProxy proxy = new WebProxy();
proxy.Address = new Uri("http://58.22.62.163:888/");

// 在发起HTTP请求前将proxy赋值给HttpWebRequest的Proxy 属性
httpRequest.Proxy = proxy;
HttpWebResponse res = (HttpWebResponse)httpRequest.GetResponse();
StreamReader reader = new StreamReader(res.GetResponseStream(), System.Text.Encoding.UTF8);
string content = reader.ReadToEnd();
reader.Close();

// 设置代理IP，参数ip的格式为是 ip：port  
private void setProxy(string ip) {
   Microsoft.Win32.RegistryKey rk = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(@"Software/Microsoft/Windows/CurrentVersion/Internet Settings", true);
   //设置代理可用 
   rk.SetValue("ProxyEnable", 1);
   //设置代理IP和端口 
   rk.SetValue("ProxyServer", ip);
   rk.Close();
}

// 取消本地的代理IP
private void disProxy() {
   Microsoft.Win32.RegistryKey rk = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(@"Software/Microsoft/Windows/CurrentVersion/Internet Settings", true);
   //设置代理可用 
   rk.SetValue("ProxyEnable", 0);
   //设置代理IP和端口 
   rk.SetValue("ProxyServer", "");
   rk.Close();
}