Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        '指定ip和端口
        Dim ipAddress As = Nothing
        (TextBox1.Text, ipAddress)
        Dim localEndPoint As New (ipAddress, TextBox2.Text)

        服务器端 = New (Net.Sockets.AddressFamily.InterNetwork, Net.Sockets.SocketType.Stream, Net.Sockets.ProtocolType.Tcp)
        服务器端.Bind(localEndPoint)
        服务器端.Listen(10)

        监听线程 = New Threading.Thread(AddressOf 监听)
        监听线程.Start()

    End Sub

    Public Sub 监听()
        While True
            连接(连接编号) = 服务器端.Accept()
            TCP线程(连接编号) = New Threading.Thread(AddressOf 接收)
            TCP线程(连接编号).Start()
        End While
    End Sub

    Public Sub 接收()
        Dim 编号 As Byte = 连接编号
        '连接编号 = 连接编号 + 1
        While True
            Dim bytesRec As Integer = 连接(编号).Receive(bytes) '接收数据
            If bytesRec > 0 Then
                data = System.Text.Encoding.ASCII.GetString(bytes, 0, bytesRec)
            End If
        End While
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        If data <> Nothing Then
            ListBox1.Items.Insert(0, data)
            data = Nothing
        End If
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        ListBox1.Items.Clear()
    End Sub

    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        On Error Resume Next
        监听线程.Abort()
        For i As Byte = 0 To 255
            TCP线程(i).Abort()
            连接(i).Shutdown(Net.Sockets.SocketShutdown.Both)
            连接(i).Close()
        Next
        服务器端.Shutdown(Net.Sockets.SocketShutdown.Both)
        服务器端.Close()
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        On Error Resume Next
        Dim msg As Byte() = System.Text.Encoding.ASCII.GetBytes(TextBox3.Text)
        Dim bytesSent As Integer = 连接(连接编号).Send(msg) '发送数据
    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        On Error Resume Next

        监听线程.Abort()
        For i As Byte = 0 To 255
            TCP线程(i).Abort()
            连接(i).Shutdown(Net.Sockets.SocketShutdown.Both)
            连接(i).Close()
        Next
        服务器端.Shutdown(Net.Sockets.SocketShutdown.Both)
        服务器端.Close()
    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    End Sub
End Class

  目前这段代码只能实现，一对一。。。如何从这段代码里实现一对多？？请教大神

又一个都是中文变量名的，不累么。
这个东西的思路是这样的，自己想想去：
对于服务器来说：
1、服务器监听时建立了一个套接字，这个套接字就是用来监听的，不干别的，不是拿来给你通讯的。
2、在有连接时，在回调中创建一个新套接字，用新的套接字和客户端通讯，这个套接字是专门给这个客户端来用的。而原来的监听套接字还在那监听。

这里有一个现成的，你看能不能用？
https://bbs.bccn.net/thread-487852-1-1.html