[RESOLVED] Crazy Counter

[Cyber-Drugs]

I have a CSV file that im reading in, which has 3 fields and un-known lines, as it is constantly updated.

Now Im looking to add a counter, and grouping system...

Here is the code I have thus far:

Dim reader As StreamReader = File.OpenText("file.txt")
Dim line As String = reader.ReadLine()
Dim a() As String
Dim j As Integer
Dim Tester As String
Dim LoopCountA As String
Dim LoopCountB aS Integer = 2
While Not (line Is Nothing)
  a = line.Split(",")
  If LoopCountA <> a(1) Then
    Tester = Tester & LoopCountB & ") "
    Tester = Tester & a(1) & ","
    Tester = Tester & a(2) & vbNewLine
    LoopCountB = 1
    LoopCountA = a(1)
  Else
    LoopCountB += 1
  End If
  line = reader.ReadLine()
End While
reader.Close()
mylabel.text = Tester

Now this sort of works... except for some reason i puts the highest number at the bottom of the list instead of next to the correct numbers. Any reason why? Anyone able to help me out?

Many thanks

[wild_bill]

What happens if you move vbNewLine?

Dim reader As StreamReader = File.OpenText("file.txt")
Dim line As String = reader.ReadLine()
Dim a() As String
Dim j As Integer
Dim Tester As String
Dim LoopCountA As String
Dim LoopCountB aS Integer = 2
While Not (line Is Nothing)
  a = line.Split(",")
  If LoopCountA <> a(1) Then
    If Tester <> Nothing then
         Tester &= vbNewLine
    End if
    Tester &= TLoopCountB & ") "
    Tester &= a(1) & ","
    Tester &= a(2)
    LoopCountB = 1
    LoopCountA = a(1)
  Else
    LoopCountB += 1
  End If
  line = reader.ReadLine()
End While
reader.Close()
mylabel.text = Tester

[Cyber-Drugs]

Still getting problems...

EG of what comes out:


1) 68,285
3) 69,291


What should be coming out:

3) 69,285
1) 69,291



Any other ideas?

[wild_bill]

Try this:

Dim sb As New System.Text.StringBuilder
        Dim reader As IO.StreamReader = IO.File.OpenText("file.txt")
        Dim sFileContents As String = reader.ReadToEnd
        reader.Close()
 
        Dim arrLines() As String = System.Text.RegularExpressions.Regex.Split(sFileContents, "/r/n")
 
        For i As Int32 = 0 To arrLines.Length - 2
            If arrLines(i).Split(","c)(0) <> arrLines(i + 1).Split(","c)(0) Then
                sb.Append(Environment.NewLine & (sb.Length - i) & ") " & arrLines(i))
            End If
        Next i
 
        mylabel.text = sb.ToString

[Cyber-Drugs]

That code prints out nothing, but a blank page wild_bill

[wild_bill]

Oops, forgot the regex options

Try this:

Dim sb As New System.Text.StringBuilder
        Dim reader As IO.StreamReader = IO.File.OpenText("file.txt")
        Dim sFileContents As String = reader.ReadToEnd
        reader.Close()
 
        Dim arrLines() As String = System.Text.RegularExpressions.Regex.Split(sFileContents, "/r/n", RegexOptions.Singleline)
 
        For i As Int32 = 0 To arrLines.Length - 2
            If arrLines(i).Split(","c)(0) <> arrLines(i + 1).Split(","c)(0) Then
                sb.Append(Environment.NewLine & (sb.Length - i) & ") " & arrLines(i))
            End If
        Next i
 
        mylabel.text = sb.ToString

[Cyber-Drugs]

It's still giving me a blank, but also the RegexOptions bit of code is underlined in blue as if VB.NET doesn't like it, or think that it is valid...

[wild_bill]

I'm being dumb today, try this:

First add
Imports System.Text.RegularExpressions

Dim arrLines() As String = Regex.Split(sFileContents, "\r\n",RegexOptions.Singleline)

[jmcilhinney]

Given that this file is of indeterminate length, I would suggest using a StringBuilder and calling Append rather than concatenating all those Strings. This has nothing really to do with your problem but it is the preferred way to deal with this many string manipulations. You could also set the initial capacity of the StringBuilder based on the size of the file. This would avoid having to reallocate memory each time the StringBuilder reached its capacity.

[wild_bill]

Is there a rule of thumb when to use a stringbuilder rather than concatenating a string? How can I set the initial capacity of a string builder?

[jmcilhinney]

You can set the initial capacity of a StringBuilder using the constructor and you can set the Capacity property at any time. There is a rule of thumb regarding string manipulation and StringBuilders. I got my information here, about half-way down. This is an MSDN article so it should be relatively reliable you would think, but other articles may have slightly different things to say perhaps.

[Cyber-Drugs]

Still giving me a blank page wild_bill...

I think I may just go back to my code, but still I don't know why it's grouping them in-correctly

[jmcilhinney]

Could you show an example of the content of the data file and the exact code you are currently using and what you expect the output to look like.?

[Cyber-Drugs]

Example contents:

0,68,284
0,68,285
0,68,286
0,69,291

It should come up like this:

3) 68,286
1) 69,291


I don't really care what the last number is to be honest, as I am just doing this to give me the ability to group by the two digit numbers, so that I can handle them seperately...

Any ideas?

[jmcilhinney]

You will need to make a few minor adjustments to this code, including the fact that you may want to convert the strings to integers.

Dim groupList As New SortedList
        Dim lineParts As String()
        Dim reader As New IO.StreamReader("file name")
 
        While reader.Peek() <> -1
            lineParts = reader.ReadLine().Split(","c)
 
            If Not groupList.ContainsKey(lineParts(1)) Then
                'Create a new list of numbers that correspond to the second number.
                groupList.Add(lineParts(1), New ArrayList)
            End If
 
            'Add the last number to the list that corresponds to the second number.
            DirectCast(groupList(lineParts(1)), ArrayList).Add(lineParts(2))
        End While
 
        Dim tempStr As New System.Text.StringBuilder
 
        'Create the output string.
        For Each groupNumber As String In groupList.GetKeyList()
            If tempStr.Length > 0 Then
                tempStr.Append(Environment.NewLine)
            End If
 
            tempStr.Append(DirectCast(groupList(groupNumber), ArrayList).Count)
            tempStr.Append(") ")
            tempStr.Append(groupNumber)
            tempStr.Append(",")
            tempStr.Append(DirectCast(groupList(groupNumber), ArrayList)(0))
        Next
 
        MessageBox.Show(tempStr.ToString())

[jmcilhinney]

Let me make that a tiny bit more efficient:

Dim groupList As New SortedList
        Dim groupSublist As ArrayList
        Dim lineParts As String()
        Dim reader As New IO.StreamReader("file name")
 
        While reader.Peek() <> -1
            lineParts = reader.ReadLine().Split(","c)
 
            If groupList.ContainsKey(lineParts(1)) Then
                groupSublist = DirectCast(groupList(lineParts(1)), ArrayList)
            Else
                'Create a new list of numbers that correspond to the second number.
                groupSublist = New ArrayList
                groupList.Add(lineParts(1), groupSublist)
            End If
 
            'Add the last number to the list that corresponds to the second number.
            groupSublist.Add(lineParts(2))
        End While
 
        Dim tempStr As New System.Text.StringBuilder
 
        'Create the output string.
        For Each groupNumber As String In groupList.GetKeyList()
            If tempStr.Length > 0 Then
                tempStr.Append(Environment.NewLine)
            End If
 
            groupSublist = DirectCast(groupList(groupNumber), ArrayList)
            tempStr.Append(groupSublist.Count)
            tempStr.Append(") ")
            tempStr.Append(groupNumber)
            tempStr.Append(",")
            tempStr.Append(groupSublist(0))
        Next
 
        MessageBox.Show(tempStr.ToString())

[Cyber-Drugs]

And now the code works

Cheers man.