VB2005实现TXT文件读写与数据处理

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim txtline, strtempL, strtempR, strMile As String
        Dim distance(100), height(100), Mile As Double
        Dim i, j, k, dotPos, zeroPos, mPos, strLength As Integer
        Dim iMile As Integer
        i = 0
        strtempL = ""
        strtempR = ""

        Dim str As IO.StreamReader = New IO.StreamReader(TxtSourcedata.Text, System.Text.Encoding.Default)
        Dim strW As IO.StreamWriter = New IO.StreamWriter(TxtTrandata.Text)
        txtline = str.ReadLine

        Do While txtline.StartsWith("B")
            dotPos = txtline.IndexOf(",")
            mPos = txtline.IndexOf(":")
            Mile = Microsoft.VisualBasic.Mid(txtline, dotPos + 2, mPos - dotPos - 1)
            Do
                txtline = str.ReadLine()
                If txtline = Nothing Then
                    Exit Do
                End If
                If txtline.StartsWith("B") Then
                    Exit Do
                End If
                i = i + 1
                strLength = txtline.Length
                dotPos = txtline.IndexOf(",")
                distance(i) = Microsoft.VisualBasic.Left(txtline, dotPos)
                distance(i) = Abs(distance(i))