/// <summary>
 /// 获取HTTP转发代理服务客户端
 /// </summary>
 /// <returns>HTTP转发代理服务客户端,失败返回null</returns>
 internal virtual client GetForwardClient()
 {
     fastCSharp.code.cSharp.tcpServer host = forwardHost;
     if (host != null)
     {
         client client = new client(host, true);
         if (client.IsStart) return client;
         client.Dispose();
     }
     return null;
 }