C#UDP同步实例

差不多有一个礼拜总算有点进步。

代码很简单，只是为了实现功能。

网络上的资源是很多，除了不能用的，就是抄来抄去，是在乏味浪费时间。

说一下代码背景：实现的功能是发送端发送消息，接收端接收后立即响应，发送端接受响应的消息。类似心跳数据，超时后更换自己IP。

　　　　　　　　就是一个备份机上运行的程序，向主机发送心跳数据，如果主机挂了（接受超时），备份机更换自己IP为主机IP。

接收端：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace HostBackupReciever
{
    public class UdpReceiver
    {
        private UdpClient _udpClient;
        private Thread _recvThread;
        
        public UdpReceiver()
        {
            _udpClient = new UdpClient(11000);
        }

        public void StartReceive() 
        {
            _recvThread = new Thread(new ThreadStart(Receive));
            _recvThread.Start();
        }

        private void Receive() {
            int count = 0;
            while (true)
            {
                try
                {
                    byte[] recvBytes = new byte[1024];
                    IPEndPoint point = new IPEndPoint(IPAddress.Any, 0);
                    recvBytes = _udpClient.Receive(ref point);
                    Console.WriteLine("I'm Receiver:" + DateTime.Now.ToString() + "--->接收消息：" + Encoding.Default.GetString(recvBytes));
                    if (recvBytes != null)
                    {
                        string sts = "北平地铁又瘫痪了";
                        byte[] bs = Encoding.Default.GetBytes(sts);
                        if (count == 10) {
                            Thread.Sleep(11000);                        
                        }
                        _udpClient.Send(bs, bs.Length, point);
                        Console.WriteLine("I'm Receiver:我已发送消息--" + sts + "第" +count + "次");
                    }
                    count++;
                
                }
                catch (Exception ex) {
                    Console.WriteLine(ex.Message);
                }        
            }
        }
    }
}

启动接收端：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace HostBackupReciever
{
    class RecerverService
    {
        public static void main(string[] args) {
            Console.WriteLine("receiver start");
            UdpReceiver receiver = new UdpReceiver();
            receiver.StartReceive();
        }
    }
}

---

发送端：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace ChooseIPDemo
{
    public class UdpChecker
    {
   
        private UdpClient _udpClient;
        private Thread _sendThread;  
        private string _sendIp;//绑定的发送ip
        private bool status = true;     //标记线程状态，中止线程运行
        public event EventHandler<CheckerEventArgs> HostDisconnectedHandler;//保存地址信息
        //
        private void OnHostDisconnected(string address)
        {
            try
            {
                Console.WriteLine("开始停止线程");
            }
            catch (Exception e)
            {
                Console.WriteLine("exception" + e.Message);
            }           
            if(HostDisconnectedHandler!=null)
                HostDisconnectedHandler(this, new CheckerEventArgs() { HostAddress = address });//直接给HostAddress赋值
            Console.WriteLine("已将address设置完毕"); 
        }
        //
        public UdpChecker(string _sendIp) 
        {   
            _udpClient = new UdpClient(12000);
            this._sendIp = _sendIp;
        }
        //
        public void StartCheck()
        {
            _sendThread = new Thread(new ThreadStart(Check));
            _sendThread.Start();
        }
        private void Check() 
        {
            int count = 0;
            while (status) {
                try
                {
                    string msg = "告诉我今天的新闻第" + count + "条";
                    IPEndPoint point = new IPEndPoint(IPAddress.Parse(_sendIp), 11000);//
                    byte[] msgBytes = Encoding.Default.GetBytes(msg);
                    _udpClient.Send(msgBytes, msgBytes.Length, point);
                    DateTime sendTime = DateTime.Now;
                    DateTime recvTime = DateTime.Now;
                    Console.WriteLine("I'm Sender:已经发送:" + msg);
                    count++;
                    byte[] recBytes = _udpClient.Receive(ref point);
                    if (recBytes != null)
                    {
                        Console.WriteLine("I'm Sender:接受的来自receiver的消息：" + Encoding.Default.GetString(recBytes));
                        recvTime = DateTime.Now;
                        _sendIp = point.Address.ToString();
                    }
                    if ((recvTime - sendTime).TotalSeconds > 5) 
                    {
                        Console.WriteLine("收取超时");
                        status = false;
                        OnHostDisconnected(_sendIp);                
                    }                    
                }
                catch (SocketException ex)
                {
                    Console.WriteLine(ex.ToString());
                }
                finally
                {
                    Thread.Sleep(2000);
                }
            }
        }
    }
    /**/
    public class CheckerEventArgs:EventArgs
    {
        private string hostAddress;
        public string HostAddress
        {
            get
            {
                return hostAddress;
            }
            set
            {
                hostAddress = value;
            }
        }
    }
}

启动发送端：(需要添加一个DLL：System.Management.DLL,不添加也可以，将ChangIP方法去掉，默认注释掉了，)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Management;
namespace ChooseIPDemo
{
    class HotBakupService
    {
        public static void Main() {
            UdpChecker checker = new UdpChecker("127.0.0.1");//目标主机IP，也是超时后备用机要切换的IP
            checker.StartCheck();
            checker.HostDisconnectedHandler += new EventHandler<CheckerEventArgs>(checker_HostDisconnectedHandler);//注册事件
            Console.ReadKey();
        }
        static void checker_HostDisconnectedHandler(object sender, CheckerEventArgs e)
        {
            Console.WriteLine("事件响应成功");
            Console.WriteLine(e.HostAddress);
            //ChangeIP(e.HostAddress);
            Console.ReadKey();
        }

       /* 

　　　　static void ChangeIP(string ipaddress)
        {
            ManagementBaseObject inPar = null;
            ManagementBaseObject outPar = null;
            ManagementClass mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
            ManagementObjectCollection moc = mc.GetInstances();
            foreach (ManagementObject mo in moc)
            {
                if (!(bool)mo["IPEnabled"])
                    continue;
                //设置ip地址和子网掩码 
                inPar = mo.GetMethodParameters("EnableStatic");
                inPar["IPAddress"] = new string[] { "192.168.1.252" };// { "192.168.1.252" ,"192.168.1.254"}1.备用 2.IP,
                inPar["SubnetMask"] = new string[] { "255.255.255.0" };
                outPar = mo.InvokeMethod("EnableStatic", inPar, null);
                //设置网关地址 
                inPar = mo.GetMethodParameters("SetGateways");
                inPar["DefaultIPGateway"] = new string[] { "192.168.1.1" }; // 1.网关;2.备用网关
                outPar = mo.InvokeMethod("SetGateways", inPar, null);
                //设置DNS 
                inPar = mo.GetMethodParameters("SetDNSServerSearchOrder");
                inPar["DNSServerSearchOrder"] = new string[] { "202.97.224.69", "202.97.224.68" }; // 1.DNS 2.备用DNS
                outPar = mo.InvokeMethod("SetDNSServerSearchOrder", inPar, null);
                break;
            }
        }*/
    }

}

结果图：第十次的时候设置较长间隔，接受时间超时，成功。