Read lines from a text file in VB.NET

Question

I have a text file format:

  *******************************************************************************
    *                              Mitecs Test Plan                               *
    *******************************************************************************

    [PRODUCTN]
    FQA=3F.4.W0,41,1
    RSC=3F.5.W4,36,1
    CFG=3F.9.2J,234,1

    [MASTERREV]
    MTP=3F.R.WM

    [FQA 13]
    FQA=3F.4.W0,41,1
    CFG=3F.9.2J,263,1

    [FQA 14]
    FQA=3F.4.W0,160,1
    CFG=3F.9.2J,315,1

I want to read text and display it in the list box, something like the below:

[PRODUCTN]
[MASTERREV]
[FQA 13]
[FQA 14]

From the above image, when I the select [FQA 14] item in list box 1 and click on the swap button, it should display in the below format in listbox 2 as

Code    Name    Version
160     FQA      3F.4.W0
315     CFG      3F.9.2J

Answer 1

One option is to use a class to hold each entry and override the ToString function to return the heading. Now you can add each entry directly to listbox1 and it will show the title to represent the item. Since each listbox item actually is an object you can cast the selected item as your entry class and read the data from the object. Here's one way to do it:

Public Class Entry
    Public Property Title As String = ""
    Public Property Data As New List(Of String)
    Public Overrides Function ToString() As String
        Return Title
    End Function
End Class

Private Sub Form4_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Dim sr As New StreamReader("textfile1.txt")
    Do Until (sr.EndOfStream)
        Dim line As String = sr.ReadLine.Trim
        If line.StartsWith("[") Then
            Dim newentry As New Entry
            newentry.Title = line
            Do Until (line = "" OrElse sr.EndOfStream)
                line = sr.ReadLine.Trim
                If Not line = "" Then
                    newentry.Data.Add(line)
                End If
            Loop
            ListBox1.Items.Add(newentry)
        End If
    Loop
End Sub

Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
    Dim selectedentry As Entry = DirectCast(DirectCast(sender, ListBox).SelectedItem, Entry)
    ListBox2.Items.Clear()
    For Each datum In selectedentry.Data
        Dim line As String() = datum.Split("=,".ToCharArray, StringSplitOptions.RemoveEmptyEntries)
        If line.Count > 2 Then
            ListBox2.Items.Add(line(2) + vbTab + line(0) + vbTab + line(1))
        Else
            ListBox2.Items.Add("   " + vbTab + line(0) + vbTab + line(1))
        End If
    Next
End Sub