Reading from and manipulating a .csv file - vb.net

Question

I have multiple .csv files for each month which go like:
01/04/2012,00:00,7.521527,80.90972,4.541667,5.774305,7,281.368
02/04/2012,00:00,8.809029,84.59028,6.451389,5.797918,7,274.0764
03/04/2012,00:00,4.882638,77.86806,1.152778,15.13611,33,127.6389
04/04/2012,00:00,5.600694,50.35417,-3.826389,15.27222,33,40.05556
The format is : Date in the form dd/mm/yy,Current time,Current temperature,Current humidity,Current dewpoint,Current wind speed,Current wind gust,Current wind bearing
The program needs to calculate the average for
temperature
humidity
wind speed
wind direction
and display them on a text box.
any ideas?
Here is what I have done so far...
Option Strict On
Option Explicit On
Imports System.IO
Imports System
Public Class Form1
Private Sub cmb1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmb1.SelectedIndexChanged
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnexit.Click
Me.Close()
End Sub
Private Sub btn1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btndata.Click
'This is for August
If cmb1.SelectedIndex = 1 Then
TextBox1.Clear()
Using reader As New StreamReader("c://temp/DailyAug12log.csv")
Dim line As String = reader.ReadLine()
Dim avgTemp As Integer
Dim fields() As String = line.Split(",".ToCharArray())
Dim fileDate = CDate(fields(0))
Dim fileTime = fields(1)
Dim fileTemp = fields(2)
Dim fileHum = fields(3)
Dim fileWindSpeed = fields(4)
Dim fileWindGust = fields(5)
Dim fileWindBearing = fields(6)
While line IsNot Nothing
counter = counter + 1
line = reader.ReadLine()
End While
avgTemp = CInt(fields(2))
avgTemp = CInt(CDbl(avgTemp / counter))
TextBox1.Text = TextBox1.Text & "Month = August" & vbCrLf & "Temperature Average: " & avgTemp & vbCrLf
End Using
End If
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim files() As String
files = Directory.GetFiles("C:\Temp", "*.csv", SearchOption.AllDirectories)
For Each FileName As String In files
cmb1.Items.Add(FileName.Substring(FileName.LastIndexOf("\") + 1, FileName.Length - FileName.LastIndexOf("\") - 1))
Next
End Sub
End Class

Answer 1

Private Class Weather
Public SampleTimeStamp AS Date
Public Temperature AS Double
Public Humidity As Double
Public WindSpeed AS Double
Public WindBearing AS Double
End Class
Sub Main
Dim samples = ReadFile("c://temp/DailyAug12log.csv")
Dim avgTemperature = samples.Average(Function(s) s.Temperature)
...
End Sub
Private Function ReadFile(ByVal fileName as String) AS List(Of Weather)
Dim samples As New List(Of Weather)
Using tfp As new TextFieldParser(filename)
tfp.Delimiters = new String() { "," }
tfp.TextFieldType = FieldType.Delimited
While Not tfp.EndOfData
Dim fields = tfp.ReadFields()
Dim sample As New Weather()
sample.SampleTimeStamp = Date.ParseExact(fields(0) & fields(1), "dd\/MM\/yyyyHH\:mm", CultureInfo.InvariantCulture)
sample.Temperature = Double.Parse(fields(2), CultureInfo.InvariantCulture)
sample.Humidity = Double.Parse(fields(3), CultureInfo.InvariantCulture)
sample.WindSpeed = Double.Parse(fields(4), CultureInfo.InvariantCulture)
sample.WindBearing = Double.Parse(fields(5), CultureInfo.InvariantCulture)
samples.Add(sample)
End While
Return samples
End Using
End Function

Answer 2

I would not use a this aprroach - if the order of the columns changes, your program will show wrong results.
I would use a good csv reader like http://kbcsv.codeplex.com/ and read the Data to a datatable. then you can calculate your resulting columns quite easily and reliablly, because you can adress each column like MyDatatable.Cooumns["Headername"].