学习VB.net串口发送与接收(二)

Imports System.IO.PortsImports System.TextPublic Class Form1    Dim WithEvents Rs232 As SerialPort    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load        For Each a As String In SerialPort.GetPortNames()            CmbCom.Items.Add(a)        Next        CmbCom.SelectedIndex = 0    End Sub    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click        Dim mPortName As String        Dim mBuandBit As Integer        Dim mDataBit As Integer        Dim mStopBit As IO.Ports.StopBits        Dim mParityBit As IO.Ports.Parity        mPortName = CmbCom.SelectedItem.ToString        mBuandBit = 9600        mDataBit = 8        mStopBit = StopBits.One        mParityBit = Parity.None        Rs232 = New SerialPort(mPortName, mBuandBit, mParityBit, mDataBit, mStopBit)        If Not Rs232.IsOpen Then            Rs232.Open()            btnSend.Enabled = True            Timer1.Interval = 100            Timer1.Enabled = True            MsgBox("~~通讯端口打开成功！~~", MsgBoxStyle.OkCancel)        Else            MsgBox("~~通讯端口打开失败（通讯端口已打开）~~", MsgBoxStyle.OkCancel)        End If    End Sub    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick        Dim Inbyte() As Byte, ReadCount As Integer        If Rs232.BytesToRead <= 0 Then Exit Sub        ReDim Inbyte(Rs232.BytesToRead - 1)        ReadCount = Rs232.Read(Inbyte, 0, Rs232.BytesToRead)        If ReadCount = 0 Then            Exit Sub        Else            For Each bData As Byte In Inbyte                txtReceive.Text += bData.ToString & vbCrLf            Next        End If    End Sub    Private Sub btnClose_Click(sender As Object, e As EventArgs) Handles btnClose.Click        If Rs232 Is Nothing OrElse Not Rs232.IsOpen Then            MsgBox("~~通讯端口尚未打开~~", MsgBoxStyle.Critical Or MsgBoxStyle.OkCancel)        Else            btnSend.Enabled = False            Timer1.Enabled = False            Rs232.Close()        End If    End Sub    Private Sub btnEnd_Click(sender As Object, e As EventArgs) Handles btnEnd.Click        If Not Rs232 Is Nothing Then            If Rs232.IsOpen Then Rs232.Close()        End If    End Sub    Private Sub btnSend_Click(sender As Object, e As EventArgs) Handles btnSend.Click        Dim bDataOut(0) As Byte        Try            bDataOut(0) = CType(txtSend.Text, Byte) '文本中输入0-255的数字            Rs232.Write(bDataOut, 0, 1)        Catch ex As Exception            MsgBox(ex.Message.ToString(), MsgBoxStyle.OkCancel)        End Try    End SubEnd Class