using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
using System.IO;
using System.Threading;
using System.Security.Cryptography;
NetworkStream stream = Client.GetStream();
结果编译错误 : The name 'Client' does not exist in the current context