extracting text from comma separated values in visual basic - vb.net

Question

I have such kind of data in a text file:
12343,M,Helen Beyer,92149999,21,F,10,F,F,T,T,T,F,F
54326,F,Donna Noble,92148888,19,M,99,T,F,T,F,T,F,T
99999,M,Ed Harrison,92147777,28,F,5,F,F,F,F,F,F,T
88886,F,Amy Pond,92146666,31,M,2,T,F,T,T,T,T,T
37378,F,Martha Jones,92144444,30,M,5,T,F,F,F,T,T,T
22444,M,Tom Scully,92145555,42,F,6,T,T,T,T,T,T,T
81184,F,Sarah Jane Smith,92143333,22,F,5,F,F,F,T,T,T,F
97539,M,Angus Harley,92142222,22,M,9,F,T,F,T,T,T,T
24686,F,Rose Tyler,92142222,22,M,5,F,F,F,T,T,T,F
11113,F,Jo Grant,92142222,22,M,5,F,F,F,T,T,T,F
I want to extract the Initial of the first name and complete surname. So the output should look like:
H. Beyer, M
D. Noble, F
E. Harrison, M
The problem is that I should not use String Split function. Instead I have to do it using any other way of string handling.
This is my code:
Public Sub btn_IniSurGen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_IniSurGen.Click
Dim vFileName As String = "C:\temp\members.txt"
Dim vText As String = String.Empty
If Not File.Exists(vFileName) Then
lbl_Output.Text = "The file " & vFileName & " does not exist"
Else
Dim rvSR As New IO.StreamReader(vFileName)
Do While rvSR.Peek <> -1
vText = rvSR.ReadLine() & vbNewLine
lbl_Output.Text += vText.Substring(8, 1)
Loop
rvSR.Close()
End If
End Sub

Answer 1

You can use the TextFieldParserClass. It will parse the file and return the results directly to you as a string array.
Using MyReader As New Microsoft.VisualBasic.FileIO.
TextFieldParser("c:\logs\bigfile")
MyReader.TextFieldType =
Microsoft.VisualBasic.FileIO.FieldType.Delimited
MyReader.Delimiters = New String() {","}
Dim currentRow As String()
'Loop through all of the fields in the file.
'If any lines are corrupt, report an error and continue parsing.
While Not MyReader.EndOfData
Try
currentRow = MyReader.ReadFields()
' Include code here to handle the row.
Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
MsgBox("Line " & ex.Message &
" is invalid. Skipping")
End Try
End While
End Using

Answer 2

For your wanted result, you may changed
lbl_Output.Text += vText.Substring(8, 1)
to
'declare this first
Dim sInit as String
Dim sName as String
sInit = vText.Substring(6, 1)
sName = ""
For x as Integer = 8 to vText.Length - 1
if vText.Substring(x) = "," Then Exit For
sName &= vText.Substring(x)
Next
lbl_Output.Text += sName & ", " & sInit
But better you have more than one lbl_Output ...

Answer 3

Something like this should work:
Dim lines As New List(Of String)
For Each s As String In File.ReadAllLines("textfile3.txt")
Dim temp As String = ""
s = s.Substring(s.IndexOf(","c) + 1)
temp = ", " + s.First
s = s.Substring(s.IndexOf(","c) + 1)
temp = s.First + ". " + s.Substring(s.IndexOf(" "c), s.IndexOf(","c) - s.IndexOf(" "c)) + temp
lines.Add(temp)
Next
The list Lines will contain the strings you need.