小菜我刚学C#，尝试编写一个简单的文件传输程序，差不多是照书上抄的，可是调试的时候老是报错，求助各位大侠，不胜感激！
一下是客户端代码，设计界面就是3框2按钮不发图了
using System;
using System.Collections.Generic;
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.Threading;
using System.IO;


namespace sj1
{
    public partial class Form1 : Form
    {
        private Socket mySock;
        private TcpClient listener;
        private System.Windows.Forms.SaveFileDialog saveFileDialog1;
        private System.Windows.Forms.TextBox textBox1;        //发送方ＩＰ
        private System.Windows.Forms.TextBox textBox2;        //发送方端口
        private System.Windows.Forms.TextBox textBox3;        //监听端口
        private System.Windows.Forms.Button button1;          //监听按钮
        private System.Windows.Forms.Button button2;          //关闭按钮
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                listener = new TcpClient(Dns.Resolve(Dns.GetHostName()).AddressList[0], Int32.Parse(textBox3.Text));
                listener.Start();
                Thread thread = new Thread(new ThreadStart(receive));
                thread.Start();
            }
            catch (Exception ee) { MessageBox.Show(ee.Message); }
        }
        private void receive()
        {
            mySock = listener.AcceptSocket();
            if (mySock.Connected)
            {
                MessageBox.Show("you have a file to save now!");
                SaveFileDialog saveFileDialog1 = new SaveFileDialog();
                saveFileDialog1.InitialDirectory = "C:\\";
                saveFileDialog1.RestoreDirectory = true;
                saveFileDialog1.Filter = "Text files(*.txt)|*.txt|All files(*.*)|*.*";
                saveFileDialog1.FilterIndex = 1;
                if (saveFileDialog1.ShowDialog() == DialogResult.OK)
                {
                    IPEndPoint ipep = (IPEndPoint)mySock.RemoteEndPoint;
                    textBox2.Text = ipep.Port.ToString();
                    textBox1.Text = ipep.Address.ToString();
                    FileStream fileStream = new FileStream(saveFileDialog1.FileName, FileMode.OpenOrCreate, FileAccess.Write);
                    int readNumber = 0;
                    byte[] bye = new byte[8];
                    NetworkStream networkStream = new NetworkStream(mySock);
                    while ((readNumber = networkStream.Read(bye, 0, 8)) > 0)
                    {
                        fileStream.Write(bye, 0, readNumber);
                        fileStream.Flush();
                    }
                    flieStream.Close();
                }
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                mySock.Close();
                listener.Stop();
                textBox1.Text = textBox2.Text = "";
            }
            catch { }
        }
    }   
}

报错内容是 类型sj1.Form1已经包含"textBox1,textBox2,textBox3,button1,button2"的定义
我尝试删除
        private System.Windows.Forms.SaveFileDialog saveFileDialog1;
        private System.Windows.Forms.TextBox textBox1;        //发送方ＩＰ
        private System.Windows.Forms.TextBox textBox2;        //发送方端口
        private System.Windows.Forms.TextBox textBox3;        //监听端口
        private System.Windows.Forms.Button button1;          //监听按钮
        private System.Windows.Forms.Button button2;          //关闭按钮
报错更多。
可怜我刚学C#根本看不懂都啥意思。
神啊救救我吧！