I'd like to see if anyone has any suggestions on making the following function faster or more efficient. This code segment reads data from a CVS file, breaks it up and writes the relevant data to a flat file. Some sample input would be:

Column A Column B
004-005 5
35 6
010-034 5


VB Code:
  1. Private Function createzonesFedEx(ByVal Filename As String, ByVal ShipType As String, ByVal Carrier As String)

  2.         Dim dash As Boolean 'determines whether or not the first column of numbers contain a dash

  3.         Dim i As Integer

  4.         Dim line As String 'line of data to be read

  5.         Dim commaArray() As String 'array of strings delimited by commas

  6.         Dim dashArray() As String ' array of strings delimited by dashes

  7.         Dim sr = New System.IO.StreamReader(Filename) ' I/O object to read data from Filename

  8.         Dim sw = New System.IO.StreamWriter(FILEPATH, True) 'I/O object to write data to FILEPATH

  9.  
  10.         line = sr.readline

  11.         While Not line Is Nothing

  12.  
  13.             commaArray = Split(line, ",")

  14.  
  15.             If (Mid(commaArray(0), 4, 1) = "-") Then

  16.                 dashArray = Split(commaArray(LBound(commaArray)), "-")

  17.                 dash = False

  18.             Else

  19.                 dash = True

  20.             End If

  21.  
  22.             For i = 0 To 7 Step 1

  23.                 Me.cboShipType.SelectedIndex = i

  24.                 Try

  25.                     sw.write(FRFIRM)

  26.                     sw.write(",")

  27.                     sw.write(Me.cboCarrier.Text)

  28.                     sw.write(",")

  29.                     sw.write(Me.cboShipType.Text)

  30.                     sw.write(",")

  31.                     sw.write(FVRSN)'Global constant

  32.                     sw.write(",")

  33.                     If (dash = False) Then

  34.                         sw.write(Format(Val(Trim(dashArray(0))), "000"))

  35.                         sw.write(",")

  36.                         sw.write(Format(Val(Trim(dashArray(1))), "000"))

  37.                         sw.write(",")

  38.                         sw.write(Format(Val(Trim(dashArray(1))), "000"))

  39.                     Else

  40.                         sw.write(Format(Val(Trim(commaArray(0))), "000"))

  41.                         sw.write(",")

  42.                         sw.write(Format(Val(Trim(commaArray(0))), "000"))

  43.                         sw.write(",")

  44.                         sw.write(Format(Val(Trim(commaArray(0))), "000"))

  45.                     End If

  46.                     sw.write(",")

  47.                     sw.write(FRSTA)'Global constant

  48.                     sw.write(",")

  49.                     sw.write(Now.Today.ToString("yyyyMMdd"))

  50.                     sw.write(",")

  51.                     sw.write(Now.Today.ToString("yyyyMMdd"))

  52.                     sw.write(",")

  53.                     sw.write(FRZAEN)'Global constant

  54.                     sw.write(",")

  55.                     sw.write(FRUSER)'Global constant

  56.                     sw.write(",")

  57.                     sw.writeline(FRWSID)'Global constant

  58.                     sw.newline()

  59.                 Catch ex As Exception

  60.                     MessageBox.Show(ex.Message)

  61.                 End Try

  62.             Next

  63.             line = sr.readline

  64.         End While

  65.         Me.cboShipType.SelectedIndex = -1

  66.         sw.Close()

  67.     End Function

This works fine, I just think it could be done better. Any suggestions? Thank you for your time.