Разобрать строку в Listbox на подстроки

Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
        Dim str1, str2() As String
        str1 = ListBox1.SelectedItem
        str2 = str1.Split(New Char() {";"})
        TextBox3.Text = (str2(0))
        TextBox4.Text = (str2(1))
        TextBox5.Text = (str2(2))
        TextBox6.Text = (str2(3))
        TextBox7.Text = (str2(4))
    End Sub

 Dim streamer As IO.StreamReader
 
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        OpenFileDialog1.ShowDialog()
        TextBox1.Text = OpenFileDialog1.FileName
    End Sub
 
 Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        streamer = IO.File.OpenText(TextBox1.Text)
        Dim mystring() As String = streamer.ReadToEnd.Split(vbNewLine)
        ListBox1.Items.AddRange(mystring)
    End Sub
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        ListBox1.Items.Add(TextBox2.Text)
    End Sub
    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Try
            ListBox1.Items.Remove(ListBox1.SelectedItem)
        Catch ex As Exception
            'do nothing'
        End Try
    End Sub
 
    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        ListBox1.Items.Clear()
    End Sub
 
    Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
        Dim saveral As Integer = 1
        Dim listpath As String = "D:\текст\1.txt"
        saveral = saveral + 1
        For i = 0 To ListBox1.Items.Count - 1
            ListBox1.SetSelected(i, True)
            Dim listwrite As System.IO.StreamWriter
            listwrite = My.Computer.FileSystem. _
            OpenTextFileWriter(listpath, True)
            listwrite.WriteLine(ListBox1.Items(i))
            listwrite.Close()
        Next
 
    End Sub
 
    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
        Try
            Dim str1, str2() As String
            str1 = ListBox1.SelectedItem
            str2 = str1.Split(New Char() {";"})
            TextBox3.Text = (str2(0))
            TextBox4.Text = (str2(1))
            TextBox5.Text = (str2(2))
            TextBox6.Text = (str2(3))
            TextBox7.Text = (str2(4))
 
        Catch ex As Exception
            MsgBox("ошибка!")
        End Try
    End Sub

Dim fn As Integer = FreeFile()
        FileOpen(fn, "Путь", OpenMode.Input)
        While Not EOF(fn)
            ListBox1.Items.Add(LineInput(fn))
        End While
        FileClose(fn)

Dim fn As Integer = FreeFile()
 FileOpen(fn, "Путь", OpenMode.Output)
        For i As Integer = 0 To Me.ListBox1.Items.Count - 1
            PrintLine(fn, Me.ListBox1.Items(i))
        Next
        FileClose(fn)

ListBox1.Items.AddRange(IO.File.ReadAllLines("C:\1.txt", System.Text.Encoding.Default))

        Dim S(ListBox1.Items.Count - 1) As String
        ListBox1.Items.CopyTo(S, 0)
        IO.File.WriteAllLines("C:\111111.txt", S)