I need some codes that able to send and read data by serialport in VB.Net
2005 beta 2. I wrote some codes and It can send data via serialport but It
cannot read what I send. I have looked up on internet and msdn and found
some codes and samples but they are also can't read serial port. . It was so
easy in VB 6.0 with mscomm object and oncommread events but now I don't
understand how it reads data from serialport. You can see the codes bellow
but while It trys to read data from serialport the program is frozen. What
is it worng and how can I fix it?
Thank you.
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
GetSerialPortNames()
End Sub
Private Sub cmdOpenPort_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles cmdOpenPort.Click
If comPort.IsOpen Then comPort.Close()
OpenPort(cboPortName.Text)
End Sub
Private Function OpenPort(ByVal PortNo As String) As Boolean
With comPort
If .IsOpen = True Then Close() 'close the port
..PortName = PortNo
..BaudRate = 9600
..Open()
End With
OpenPort = True
End Function
Sub GetSerialPortNames()
' Show all available COM ports.
For Each sp As String In My.Computer.Ports.SerialPortNames
cboPortName.Items.Add(sp)
Next
End Sub
Private Sub cmdSend_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles cmdSend.Click
SendSerialData(txtOutput.Text)
End Sub
Sub SendSerialData(ByVal data As String)
' Send strings to a serial port.
If comPort.IsOpen = False Then
MsgBox("The port is not open")
Else
comPort.WriteLine(data)
End If
End Sub
Private Sub cmdRead_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles cmdRead.Click
txtOutput.Text = ReveiveSerialData()
End Sub
Function ReveiveSerialData() As String
' Receive strings from a serial port.
Dim returnStr As String = ""
Do
Dim Incoming As String = comPort.ReadLine
If Incoming Is Nothing Then
Exit Do
Else
returnStr &= Incoming & vbCrLf
End If
Loop
Return returnStr
End Function
End Class
