掃描裝置上的GPS是哪一個COM

在"在PDA上開發GPS的程式問題這篇文章中，有提到要如何去看GPS是在哪一個COM Port上面；一般來說有兩個方式，一個是自己去掃描，另一種方式就是借助別人的軟體去看了；下面這邊我做了一個簡單的掃描程式，有興趣的朋友可以參考看看

Imports System.IO.Ports
Imports System.Text

Public Class Form1
    Dim strPortName As String = ""
    Dim strTmp As String = ""
    Dim B(199) As Byte
    Dim intReturn As Integer = 0

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        SerialPort1.BaudRate = 4800
        SerialPort1.DataBits = 8
        SerialPort1.Handshake = Handshake.None
        SerialPort1.StopBits = StopBits.One
        SerialPort1.Parity = Parity.None
        SerialPort1.ReadTimeout = 2500
        For Each s As String In SerialPort.GetPortNames
            SerialPort1.PortName = s
            Try
                SerialPort1.Open()
                Threading.Thread.Sleep(200)
                intReturn = SerialPort1.Read(B, 0, B.Length)
                If intReturn > 0 Then
                    strTmp = Encoding.ASCII.GetString(B, 0, intReturn)
                    If strTmp.IndexOf("$GP") >= 0 Then
                        strPortName = SerialPort1.PortName
                        TextBox1.Text = strTmp
                    End If
                End If
                SerialPort1.Close()
            Catch ex As Exception
                If SerialPort1.IsOpen Then SerialPort1.Close()
            End Try
        Next
    End Sub
End Class