C#实现Upd通信（二）--socket通信配合订阅者模式广播及收发信息

上一节讲的是简单的socket通信，为了提高复用率，整理为一个帮助类，并加入订阅者模式（想要接受通知的类或者界面只要注册了该类，则无需通过一层层传递的方式传递数据，具体下次写一篇具体说明），方便本机电脑广播的方式发生信息给多台用户，并在多个界面能够接到远程设备返回的数据。

所有代码：
https://download.csdn.net/download/Yyuanyuxin/13026074
帮助类代码：

private static SocketHelper instants;
public static SocketHelper Instants
{
    get
    {
        if (instants == null)
            instants = new SocketHelper();
        return instants;
    }
}
private Socket _server;
public IPAddress Ip;
public int Port;
public string Mac;
public Dictionary<IPAddress, int> ClientIpAndPort=new Dictionary<IPAddress, int>();

public bool Init(string ip = "", string port = "")
{
    try
    {
        if (!IPAddress.TryParse(ip == "" ? GetLocalIP() : ip, out Ip))
        {
            MessageBox.Show("获取本机信息错误！");
            return false;
        }
        if (!int.TryParse(port == "" ? GetLocalValidPort() : port, out Port))
        {
            MessageBox.Show("本机没有可用的端口！");
            return false;
        }
        Mac = GetLocalMac();
        if (Mac == "")
        {
            MessageBox.Show("获取本机MAC错误！");
            return false;
        }
        _server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
        _server.Bind(new IPEndPoint(Ip, Port));//绑定端口号和IP
        Thread t1 = new Thread(ReceiveMsg);//开启接收消息线程
        t1.IsBackground = true;
        t1.Start();
        return true;
    }
    catch (Exception ex)
    {
        return false;
    }

}
/// <summary>
/// 接收发送给本机ip对应端口号的数据报
/// </summary>
public void ReceiveMsg()
{
    while (true)
    {
        EndPoint port = new IPEndPoint(IPAddress.Any, 0);//用来保存发送方的ip和端口号
        byte[] buffer = new byte[1024];
        int length = _server.ReceiveFrom(buffer, ref port);//接收数据报
        var port1 = port as IPEndPoint;
        string message = Encoding.UTF8.GetString(buffer, 0, length);
        if (NotifyEvent != null)
        {
            NotifyEvent(this, port1, message );
        }
    }
}
public void SendMsg(object msg)
{
    Thread t2 = new Thread(new ParameterizedThreadStart(SendMsgThread));//开启发送消息线程
    t2.IsBackground = true;
    if (msg is string msgString)
    {
        t2.Start(Encoding.UTF8.GetBytes(msgString));
    }
    else if (msg is byte[] msgbyte)
    {
        t2.Start(msgbyte);
    }
}
/// <summary>
/// 向特定ip的主机的端口发送数据报
/// </summary>
private void SendMsgThread(object msg)
{
    IPAddress curIp =null;
    try
    {
        if (ClientIpAndPort == null) return;
        if (msg is byte[] buffle)
        {
            foreach (var ip in ClientIpAndPort.Keys)
            {
                curIp = ip;
                EndPoint port = new IPEndPoint(ip, ClientIpAndPort[ip]);
                _server.SendTo(buffle, port);
            }
        }
    }
    catch (Exception ex)
    {
        if (curIp != null && ClientIpAndPort.ContainsKey(curIp))
            ClientIpAndPort.Remove(curIp);
        MessageBox.Show(ex.Message);
        
    }
    
    

}
public bool  AddClientIpAndPort(string ipString,string portString)
{
    if (IPAddress.TryParse(ipString, out IPAddress ip)&& int.TryParse(portString,out int port))
    {
        if (ClientIpAndPort.ContainsKey(ip))
        {
            ClientIpAndPort[ip] = port;
        }
        else
        {
            ClientIpAndPort.Add(ip, port);
        }
        return true;
    }
    return false;
}
/// <summary>
///  // 获得本机局域网IP地址 
/// </summary>
/// <returns></returns>
private string GetLocalIP()
{
    IPAddress[] AddressList = Dns.GetHostByName(Dns.GetHostName()).AddressList;
    if (AddressList.Length < 1)
    {
        return "";
    }
    return AddressList[0].ToString();
}
/// <summary>
/// 获取本地有效的端口号
/// </summary>
/// <returns></returns>
private string GetLocalValidPort()
{
    IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
    //返回本地计算机上的所有Tcp监听程序    
    var ipsTcp = properties.GetActiveTcpListeners();
    //返回本地计算机上的所有UDP监听程序     
    var ipsUdp = properties.GetActiveUdpListeners();
    for (int i = 1024; i < 5000; i++)
    {
        if (ClientIpAndPort.ContainsValue(i)) continue;
        foreach (var ip in ipsTcp)
        {
            if (ip.Port == i) continue;
            foreach (var ip2 in ipsUdp)
            {
                if (ip2.Port != i)
                {
                    return i.ToString();
                }
            }
        }
        if (i == 4999)
        {
            return "";
        }

    }
    return "";
}
public string GetLocalMac()
{
    ManagementObjectSearcher query = new ManagementObjectSearcher("SELECT * FROM Win32_NetworkAdapterConfiguration");
    ManagementObjectCollection queryCollection = query.Get();
    foreach (ManagementObject mo in queryCollection)
    {
        if (mo["IPEnabled"].ToString() == "True")
            return mo["MacAddress"].ToString();
    }
    return "";
}
#region 用于通知订阅者
private NotifyEventHandler NotifyEvent;
public void AddObserver(NotifyEventHandler observer) 
{
    NotifyEvent += observer;
}
public void RemoveObserver(NotifyEventHandler observer)
{
    NotifyEvent -= observer;
}
#endregion

订阅者接口

public delegate void NotifyEventHandler(SocketHelper sender, IPEndPoint port,object data);
public interface IMySocketObserver
{
   void Receive(SocketHelper sender, IPEndPoint port, object data);
}

使用
初始化：

SocketHelper socketHelper = SocketHelper.Instants;
socketHelper.AddObserver(Receive);
if(socketHelper.Init(textBox1.Text, textBox2.Text))
{
    textBox1.Text = socketHelper.Ip.ToString();
    textBox2.Text = socketHelper.Port.ToString();
}

发送广播信息：

socketHelper.AddClientIpAndPort(textBox4.Text, textBox3.Text);
socketHelper.SendMsg(richTextBox1.Text);

订阅者（例如）：

public partial class Form1 : Form, IMySocketObserver
{
	public void Receive(SocketHelper sender, IPEndPoint port, object data)
        {
            this.Invoke((EventHandler)delegate 
            {
                richTextBox2.AppendText(port+"  :"+data.ToString()+ "\r\n");
            });
        }
}

本文地址：https://blog.csdn.net/Yyuanyuxin/article/details/109244484