写一个vb.net的tcp/socket 服务器和客户端都包涵的程序

在VB.NET中编写TCP套接字服务器和客户端程序，你需要了解基本的网络编程原理，并熟悉如何使用System.Net命名空间下的TcpClient和TcpServer类。这里是一个简单的示例：

**服务器端（Server.vb）：**

Imports System.Net
Imports System.IO

Public Class ServerForm
    Private server As TcpListener
    Private client As TcpClient

    Public Sub New()
        InitializeComponent()

        ' 创建监听器并开始监听
        Dim ip As String = "localhost" ' 可修改为你希望监听的IP地址
        Dim port As Integer = 12345 ' 可修改为你希望的端口号
        server = New TcpListener(IPAddress.Parse(ip), port)
        server.Start()

        ' 监听新的连接请求
        AddHandler server.Accepted, AddressOf AcceptClient
    End Sub

    Private Sub AcceptClient(sender As Object, e As NetworkStreamEventArgs)
        ' 当有新客户端连接时，创建一个新的线程处理请求
        Dim newClient As TcpClient = e.ConnectedSocket
        Dim stream As NetworkStream = newClient.GetStream()
        Dim buffer(1024) As Byte

        ' 在新线程中处理客户端通信
        Dim clientThread As New Thread(AddressOf HandleClientCommunication)
        clientThread.Start(stream)
    End Sub

    Private Sub HandleClientCommunication(ByVal stream As NetworkStream)
        Try
            ' 读取和发送数据
            While True
                Dim bytesRead As Integer = stream.Read(buffer, 0, buffer.Length)
                If bytesRead > 0 Then
                    Dim message As String = Encoding.ASCII.GetString(buffer, 0, bytesRead)
                    Console.WriteLine("Received from Client: " & message)
                    stream.Write(Encoding.ASCII.GetBytes("Message received"), 0, message.Length)
                Else
                    ' 客户端断开连接，关闭流
                    stream.Close()
                    Exit While
                End If
            End While
        Catch ex As Exception
            Console.WriteLine("Error: " & ex.Message)
        Finally
            ' 关闭客户端连接
            stream.Close()
            client = Nothing
        End Try
    End Sub
End Class

**客户端（Client.vb）：**

Imports System.Net
Imports System.IO

Public Class ClientForm
    Private client As TcpClient
    Private stream As NetworkStream

    Public Sub New()
        InitializeComponent()

        ' 连接到服务器
        Dim ipAddress As String = "localhost" ' 修改为你服务器的实际IP地址
        Dim port As Integer = 12345 ' 修改为你服务器使用的端口号
        client = New TcpClient()
        client.Connect(ipAddress, port)

        ' 获取连接后的网络流
        stream = client.GetStream()

        ' 发送一条消息到服务器
        Dim sendMessage As String = "Hello Server"
        SendData(Encoding.ASCII.GetBytes(sendMessage))

        ' 接收服务器响应
        ReceiveData()
    End Sub

    Private Sub SendData(ByVal data As Array)
        Dim bytes Sent As Integer = stream.Write(data, 0, data.Length)
        Console.WriteLine("Sent: " & Encoding.ASCII.GetString(data))
    End Sub

    Private Sub ReceiveData()
        Dim buffer(1024) As Byte
        Dim bytesRead As Integer = stream.Read(buffer, 0, buffer.Length)
        If bytesRead > 0 Then
            Dim message As String = Encoding.ASCII.GetString(buffer, 0, bytesRead)
            Console.WriteLine("Received from Server: " & message)
        Else
            ' 服务器断开连接
            MessageBox.Show("Connection closed by server.")
        End If
    End Sub
End Class

在实际项目中，你可能需要将上述代码封装到类库中以便更好地管理和复用。运行服务器后，你可以从客户端实例化一个`TcpClient`并连接到它。