C# 关于代理检测的问题(难,真的难)?
现在一个程序
通过我自已写的方法来判断是代理是否正常工作,核心代码如下:

C# code

public void Connect(string server, int port, Proxy proxy, ConnectCallBack callback){    this._client = new TcpClient();    try    {        this._server = server;        this._port = port;        this._callback = callback;        this._proxy = proxy;        this._client.BeginConnect(proxy.Server, proxy.Port, new AsyncCallback(this.Connected), null);    }    catch    {    }}private void Connected(IAsyncResult ar){    try    {        this._client.EndConnect(ar);        NetworkStream stream = this._client.GetStream();        StreamWriter writer = new StreamWriter(stream);        writer.WriteLine(string.Format("CONNECT {0}:{1} HTTP/1.1", this._proxy.Server, this._proxy.Port));        writer.WriteLine("Accept: */*");        writer.WriteLine("Content-Type: text/html");        writer.WriteLine("Proxy-Connection: Keep-Alive");        if (!string.IsNullOrEmpty(this._proxy.User))        {            string s = this._proxy.User + ":" + this._proxy.Password;            writer.WriteLine("Proxy-Authorization: Basic " + Convert.ToBase64String(Encoding.ASCII.GetBytes(s)));        }        writer.WriteLine("Content-length: 0");        writer.WriteLine();        writer.Flush();        bool isSuccess = false;        string msg = "代理服务器错误";        StreamReader reader = new StreamReader(stream);        for (string str4 = reader.ReadLine(); (str4 != null) && (str4.Length > 0); str4 = reader.ReadLine())        {            if (str4.ToUpper().IndexOf("HTTP/1.0") > -1)            {                string[] strArray = str4.Split(new char[] { ' ' });                if (strArray.Length > 1)                {                    if (strArray[1] == "200")                    {                        isSuccess = true;                        msg = "代理服务器工作正常";                    }                    else                    {                        msg = "代理服务器错误 错误码" + strArray[1];                    }                }            }        }        this._callback(isSuccess, msg);    }    catch (Exception)    {        this._callback(false, "连接代理服务器失败");    }}

服务器返回状态码403(隐藏),程序认为代理不可用~
但是QQ代理测试是正常的,也是可用的,请问上述方法检测代理是否有问题,最好有demo可以参考

[解决办法]
你先别用qq代理测试 你直接ping一下试试
[解决办法]
网络编程的主要工作量大多在异常处理了。测试，异常会花很多时间。常有很古怪的问题。楼主仔细找找吧。
[解决办法]
帮你顶一下吧！！
[解决办法]
利用telnet [ip] [port]测试

程序代码就不帮你写啦