bonjour

pouvez vous me dire à quoi sert la ligne 

Sender.dispose

Dans le code suivant

sachant que si j’enlève cette ligne ,que j’exécute et que je coche la checkbox3 ,lasouris prend la forme d’une croix mais que je ne peux pas supprimer les lapins

si je laisse la ligne je peux

  Public decalx, decaly As Integer

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.AllowDrop = True
    End Sub

    Private Sub Lapin_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Lapin.MouseDown
        If CheckBox3.Checked = True Then
            sender.dispose()
            Dim n As Integer = 0
            Dim truc As Control
            For Each truc In Controls
                If TypeOf truc Is PictureBox Then
                    n = n + 1
                End If
            Next truc
            If n = 0 Then
                n = MsgBox("Tous les lapins sont trucidés", MsgBoxStyle.Critical, "Mission accomplie")
                End
            End If
        ElseIf CheckBox2.Checked = False Then
            decalx = e.X
            decaly = e.Y
            Lapin.DoDragDrop(Lapin.Image, DragDropEffects.All)
        End If
    End Sub

    Private Sub Form1_DragEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles MyBase.DragEnter
        If CheckBox1.Checked = True Then
            e.Effect = DragDropEffects.Copy
        Else
            e.Effect = DragDropEffects.Move
        End If
    End Sub

    Private Sub Form1_DragDrop(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles MyBase.DragDrop
        If CheckBox1.Checked = True Then
            Dim toto As New PictureBox
            toto.Width = 32
            toto.Height = 32
            toto.Image = e.Data.GetData(DataFormats.Bitmap)
            Controls.Add(toto)
            toto.Left = e.X - Me.Left - decalx
            toto.Top = e.Y - Me.Top - decaly - 30
            AddHandler toto.MouseDown, AddressOf Lapin_MouseDown
        Else
            Lapin.Left = e.X - Me.Left - decalx - 3
            Lapin.Top = e.Y - Me.Top - decaly - 30
        End If
    End Sub

    Private Sub CheckBox3_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox3.CheckedChanged
        If CheckBox3.Checked = True Then
            Me.Cursor = Cursors.Cross
            CheckBox1.Checked = False
            CheckBox2.Checked = False
        Else
            Me.Cursor = Cursors.Arrow
        End If
    End Sub

    Private Sub CheckBox1_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
        If CheckBox3.Checked = True Then
            CheckBox1.Checked = False
        End If
    End Sub

    Private Sub CheckBox2_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CheckBox2.CheckedChanged
        If CheckBox3.Checked = True Then
            CheckBox2.Checked = False
        End If
    End Sub

    Private Sub Lapin_Click(sender As System.Object, e As System.EventArgs) Handles Lapin.Click

    End Sub
End Class