C#udp通信_c# udpclient怎么防止端口被占用

本人是做嵌入式开发的，上位机只会一点，入门阶段，下面程序是自己做的测试程序一部分

1. 包含空间

​
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
 
​

2. 新建socket

private void button1_Click(object sender, EventArgs e)
        {
            if (button1.Text == "connect")
            {
                try
                {
                    client = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
                    client.Bind(new IPEndPoint(IPAddress.Parse(txtIP.Text), int.Parse(txtPort.Text)));
 
                    //t = new Thread(sendMsg);
 
 
                    t2 = new Thread(ReciveMsg);
                    t2.Start();
                    buttonen(true);
                    button1.Text = "disconnect";
                }
                catch
                {
                    MessageBox.Show("connect message is error", "错误");//出错提示
                }
     
            }
            else 
            {
                t2.Abort();
                client.Close();
                button1.Text = "connect";
                buttonen(false);
 
            }

3.发送数据

        private void button2_Click(object sender, EventArgs e)
        {
            byte[] Data = new byte[((sendBox1.Text.Length) / 2)+36];//作用同上集
 
            //EndPoint point = new IPEndPoint(IPAddress.Parse("192.168.3.29"), 16800);
            EndPoint point = new IPEndPoint(IPAddress.Parse(sendboxip.Text), int.Parse(sendport.Text));
 
            if (radioButton2.Checked)                //字符模式
            {
                try
                {
                    string msg = sendBox1.Text;
                    client.SendTo(Encoding.Default.GetBytes(msg), point);
                }
                catch
                {
                    MessageBox.Show("send message is error", "错误");//出错提示
                }
            }
            else
            {
                try
                {
                    if (0 == (sendBox1.Text.Length) % 2)
                    {
                        for (int i = 0; i < (sendBox1.Text.Length) / 2; i++)
                        {
                            Data[i] = Convert.ToByte(sendBox1.Text.Substring(i * 2, 2), 16);
                           // client.SendTo(Data, point);
                        }
                        client.SendTo(Data, point);
                       // client.Send(Data, 0);
                    }
                    else
                        MessageBox.Show("send message len is error", "错误");//出错提示
 
                }
                catch
                {
                    MessageBox.Show("send message is error", "错误");//出错提示
                }
              
    
            }
  
 
 
 
        }

3.接收udp数据

        void ReciveMsg()
        {
            while (true)
            {
                EndPoint point = new IPEndPoint(IPAddress.Any, 0);//用来保存发送方的ip和端口号
                byte[] buffer = new byte[2048];
                int length = client.ReceiveFrom(buffer, ref point);//接收数据报
                recv = "";
                recv += Encoding.UTF8.GetString(buffer, 0, length);
                //recv += "\r\n";
                if(length > 0)
                {
                    if (radioButton3.Checked)               //字符形似
                    {
                        AddContent(recv, richTextBox1);
                        AddContentline(richTextBox1);
                    }
                    else
                    {
                        for (int i = 0; i < length; i++)
                        {
                            string str = Convert.ToString(buffer[i], 16).ToUpper();//转换为大写十六进制字符串
                            AddContent(str, richTextBox1);
                            //textBox1.AppendText("0x" + (str.Length == 1 ? "0" + str : str) + " ");//空位补“0” 
                        }
                        AddContentline(richTextBox1);
                    }
                }
                    
        
                //txtReciv.Text += recv;
            }
        }