如果出现错误，请更改代理;如果已经使用代理，请更改代理

本文关键字：代理 如果 错误 | 更新日期: 2023-09-27 18:09:54

所以我不确定如何使系统喜欢为每个web请求选择其他代理&如果出现错误，请选择其他代理。我没有为它编写任何代码，但我希望有人可以为我做。

谢谢!:)

如果出现错误，请更改代理;如果已经使用代理，请更改代理

就这么做

需要一个简单的类

public class IpAndPort
{
    public string IpAddress { get; set; }
    public string Port { get; set; }
}

现在把代理放到列表中:

var proxies = new List<IpAndPort>
{
     new IpAndPort{ IpAddress = "192.168.1.1", Port = "8012" },
     new IpAndPort{ IpAddress = "192.118.1.2", Port = "8072" },
     new IpAndPort{ IpAddress = "222.167.1.7", Port = "9012" },
     new IpAndPort{ IpAddress = "172.145.1.4", Port = "82" }
     //...
}

现在为web请求

调用以下方法
var concurrentBag = new ConcurrentBag<IpAndPort>(proxies);
GetProxyWebResponse(txtUrl.Text.Trim(), concurrentBag);

private async Task<string> GetProxyWebResponse(string url, ConcurrentBag<IpAndPort> concurrentBag)
{   
      while (!concurrentBag.IsEmpty)
      {
           IpAndPort proxy;
           if (!concurrentBag.TryTake(out proxy)) continue;
           try
           {
                while (true)
                {   
                     if (!SocketConnect(proxy.IpAddress, Convert.ToInt32(proxy.Port)))
                     {
                          break;
                     }
                     var webProxy = new WebProxy(proxy.IpAddress, proxy.Port)
                     {
                          BypassProxyOnLocal = false,
                          Credentials = CredentialCache.DefaultCredentials
                     };
                     var request = (HttpWebRequest)WebRequest.Create(url);
                     request.Proxy = webProxy;          
                     request.Proxy = GlobalProxySelection.GetEmptyWebProxy();
                     try
                     {
                          var response = (HttpWebResponse)request.GetResponse();
                          string error;
                          var responseFromServer = GetResponseText(response, out error);
                          //do work with responseFromServer 
                     }
                     catch (Exception ex)
                     {
                          //ExceptionLogger.CreateFile(ex);
                     }
                     await Task.Delay(2000);
               }                        
         }
         catch (Exception ex)
         {
              Console.WriteLine(ex.Message);
         }
         await Task.Delay(6000);
    }
    return string.Empty;
}

帮助方法

public static bool SocketConnect(string host, int port)
{
    var is_success = false;
    try
    {
         var connsock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
         connsock.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.SendTimeout, 200);
         Thread.Sleep(500);
         var hip = IPAddress.Parse(host);
         var ipep = new IPEndPoint(hip, port);
         connsock.Connect(ipep);
         if (connsock.Connected)
         {
             is_success = true;
         }
         connsock.Close();
     }
     catch (SocketException)
     {
         is_success = false;
     }
     catch (Exception)
     {
         is_success = false;
     }
     return is_success;
}
private static string GetResponseText(HttpWebResponse response, out string error)
{
     error = string.Empty;
     if (response == null)
     {
         error = "Listed proxy servers did not responding.";
         return null;
     }
     var responseFromServer = string.Empty;
     var responceStream = response.GetResponseStream();
     if (responceStream != null)
     {
         using (var reader = new StreamReader(responceStream))
         {
             responseFromServer = reader.ReadToEnd();
         }
     }
     return responseFromServer;
}

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