Compter les item d'une listview

Imports System.IO
Public Class Form1
    Dim bf As New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter()
    Dim ligne As Integer
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        Using fs As New System.IO.FileStream("sauvegarde.txt", IO.FileMode.Create)
            bf.Serialize(fs, New ArrayList(ListView1.Items))
        End Using
    End Sub
    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        Button1.Text = "Ajouter item"
        Button2.Text = "Supprimer item"
        Button3.Text = "Ouvrir Form2"
        Button4.Text = "Enregistrer données"
        Label4.Text = "Items cochés"
        'Le ListView1 existe
        ListView1.View = View.Details
        ListView1.CheckBoxes = True
        ListView1.Columns.Add("Nom", 80, HorizontalAlignment.Left)
        ListView1.Columns.Add("Prénom", 80, HorizontalAlignment.Left)
        ListView1.Columns.Add("Année naissance", 100, HorizontalAlignment.Left)
        Try
            If File.Exists("sauvegarde.txt") Then
                Using fs As New System.IO.FileStream("sauvegarde.txt", IO.FileMode.Open)
                    ListView1.Items.AddRange(bf.Deserialize(fs).ToArray(GetType(ListViewItem)))
                End Using
            End If
        Catch
        End Try
    End Sub
    'ajoute item
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        If Textnom.Text = "" Or Textprenom.Text = "" Or Textnaissance.Text = "" Then Exit Sub
        Dim MyLine As ListViewItem = New ListViewItem(New String() {Textnom.Text, Textprenom.Text, Textnaissance.Text})
        ListView1.Items.Add(MyLine)
    End Sub
    'supprime item
    Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
        If ListView1.SelectedItems.Count > 0 Then
            ListView1.Items.RemoveAt(ligne)
        End If
    End Sub
    'selection ligne
    Private Sub ListView1_SelectedIndexChanged(sender As System.Object, e As System.EventArgs) Handles ListView1.SelectedIndexChanged
        If ListView1.SelectedItems.Count > 0 Then
            ligne = ListView1.SelectedItems(0).Index
        End If
    End Sub
    'checke par item
    Private Sub ListView1_ItemChecked(ByVal sender As Object, ByVal e As System.Windows.Forms.ItemCheckedEventArgs) Handles ListView1.ItemChecked
        If ListView1.Items.Count > 0 Then ' si listview1 non vide
            For j = 0 To ListView1.Items.Count - 1
                ' colore suivant case cochée par item
                ListView1.Items(j).ForeColor = IIf(ListView1.Items(j).Checked = False, Color.Black, Color.Red)
            Next j
            Label4.Text = ListView1.CheckedItems.Count & " sélectionné" & IIf(ListView1.CheckedItems.Count > 1, "s", "") 'compte les fichiers selectionnés
        End If
    End Sub
    'ouvrir Form2
    Private Sub Button3_Click(sender As System.Object, e As System.EventArgs) Handles Button3.Click
        Form2.ShowDialog()
    End Sub
    'enregistrer données
    Private Sub Button4_Click(sender As System.Object, e As System.EventArgs) Handles Button4.Click
        Using fs As New System.IO.FileStream("sauvegarde.txt", IO.FileMode.Create)
            bf.Serialize(fs, New ArrayList(ListView1.Items))
        End Using
    End Sub
End Class

Imports System.IO
Public Class Form2
    Dim bf As New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter()
    Private Sub Form2_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        'Le ListView1 existe
        ListView1.View = View.Details
        ListView1.CheckBoxes = True
        ListView1.Columns.Add("Nom", 80, HorizontalAlignment.Left)
        ListView1.Columns.Add("Prénom", 80, HorizontalAlignment.Left)
        ListView1.Columns.Add("Année naissance", 100, HorizontalAlignment.Left)
        ListView1.Items.Clear()
        Try
            If File.Exists("sauvegarde.txt") Then
                Using fs As New System.IO.FileStream("sauvegarde.txt", IO.FileMode.Open)
                    ListView1.Items.AddRange(bf.Deserialize(fs).ToArray(GetType(ListViewItem)))
                End Using
            End If
        Catch
        End Try
    End Sub
End Class

 
Dim ligne As Integer
 'selection ligne
    Private Sub ListView1_SelectedIndexChanged(sender As System.Object, e As System.EventArgs) Handles ListView1.SelectedIndexChanged
        If ListView1.SelectedItems.Count > 0 Then
            ligne = ListView1.SelectedItems(0).Index
        End If
    End Sub
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        MsgBox(ListView1.Items(ligne).Text)
        MsgBox(ListView1.Items(ligne).SubItems(1).Text)
        MsgBox(ListView1.Items(ligne).SubItems(2).Text)
    End Sub