VB.net使用SerialPort类访问串口

Public Class Form1
Dim mySerialPort As New System.IO.Ports.SerialPort
Delegate Sub DataShow(ByVal myString As String)

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
mySerialPort.Write("at+wmsn" & vbCrLf)
End Sub

Private Sub Form1_Disposed(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Disposed
If mySerialPort.IsOpen Then
mySerialPort.Close()
End If
End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
With mySerialPort
.PortName = "COM3"
.DataBits = 8
.StopBits = IO.Ports.StopBits.One
.Parity = IO.Ports.Parity.None
.BaudRate = 115200
.RtsEnable = True
.ReceivedBytesThreshold = 1
AddHandler mySerialPort.DataReceived, AddressOf SerialPort_DataReceived
.Open()
End With
End Sub

Sub SerialPort_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs)
Dim sp As IO.Ports.SerialPort = sender
Dim s As String = sp.ReadExisting
Invoke(New DataShow(AddressOf SerialPort_DataShow), New Object() {s})
End Sub

Private Sub SerialPort_DataShow(ByVal myString As String)
TextBox1.Text = TextBox1.Text & myString
End Sub
End Class