1    private IPEndPoint ipLocalPoint;
2    private EndPoint RemotePoint;
3    private Socket mySocket;
4    private bool RunningFlag = false; 

1    private string getIPAddress()
2    {
3    // 获得本机局域网IP地址
4    IPAddress[] AddressList = Dns.GetHostByName(Dns.GetHostName()).AddressList;
5    if (AddressList.Length < 1)
6    {
7    return "";
8    }
9    return AddressList[0].ToString();
10    } 

15    private int getValidPort(string port)
16    {
17    int lport;
18    //测试端口号是否有效
19    try
20    {
21    //是否为空
22    if (port == "")
23    {
24    throw new ArgumentException(
25    "端口号无效，不能启动DUP");
26    }
27    lport = System.Convert.ToInt32(port);
28    }
29    catch (Exception e)
30    {
31    //ArgumentException,
32    //FormatException,
33    //OverflowException
34    Console.WriteLine("无效的端口号：" + e.ToString());
35    this.tbMsg.AppendText("无效的端口号：" + e.ToString() + "\n");
36    return -1;
37    }
38    return lport;
39    }
40
41
42    private IPAddress getValidIP(string ip)
43    {
44    IPAddress lip = null;
45    //测试IP是否有效
46    try
47    {
48    //是否为空
49    if (!IPAddress.TryParse(ip, out lip))
50    {
51    throw new ArgumentException(
52    "IP无效，不能启动DUP");
53    }
54    }
55    catch (Exception e)
56    {
57    //ArgumentException,
58    //FormatException,
59    //OverflowException
60    Console.WriteLine("无效的IP：" + e.ToString());
61    this.tbMsg.AppendText("无效的IP：" + e.ToString() + "\n");
62    return null;
63    }
64    return lip;
65    } 

66    //得到本机IP，设置UDP端口号
67    ip = getValidIP(tbLocalIP.Text);
68    port = getValidPort(tbLocalPort.Text);
69    ipLocalPoint = new IPEndPoint(ip, port);
70
71    //定义网络类型，数据连接类型和网络协议UDP
72    mySocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
73
74    //绑定网络地址
75    mySocket.Bind(ipLocalPoint);
76
77    //得到客户机IP
78    ip = getValidIP(tbRemoteIP.Text);
79    port = getValidPort(tbRemotePort.Text);
80    IPEndPoint ipep = new IPEndPoint(ip, port);
81    RemotePoint = (EndPoint)(ipep);
82
83    //启动一个新的线程，执行方法this.ReceiveHandle，
84    //以便在一个独立的进程中执行数据接收的操作
85
86    RunningFlag = true;
87    Thread thread = new Thread(new ThreadStart(this.ReceiveHandle));
88    thread.Start(); 

89    //定义一个委托
90    public delegate void MyInvoke(string strRecv);
91    private void ReceiveHandle()
92    {
93    //接收数据处理线程
94    string msg;
95    byte[] data=new byte[1024];
96    MyInvoke myI = new MyInvoke(UpdateMsgTextBox);
97    while (RunningFlag)
98    {
99
100    if (mySocket == null || mySocket.Available < 1)
101    {
102    Thread.Sleep(200);
103    continue;
104    }
105    //跨线程调用控件
106    //接收UDP数据报，引用参数RemotePoint获得源地址
107    int rlen = mySocket.ReceiveFrom(data, ref RemotePoint);
108    msg = Encoding.Default.GetString(data, 0, rlen);
109    tbMsg.BeginInvoke(myI, new object[]{RemotePoint.ToString() + " : " + msg});
110
111    }
112    }
113    private void btSend_Click(object sender, EventArgs e)
114    {
115    string msg;
116    msg = tbSendMsg.Text;
117    //发送UDP数据包
118    byte[] data = Encoding.Default.GetBytes(msg);
119    mySocket.SendTo(data, data.Length, SocketFlags.None, RemotePoint);
120    }
121    private void UpdateMsgTextBox(string msg)
122    {
123    //接收数据显示
124    this.tbMsg.AppendText( msg + "\n");
125    }