Coding Visual Basic Menghitung Faktorial

Public Class Hitung_Faktorial
    Dim nilai As Long
    Dim faktorial As Long

    Private Sub BtnHitung_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnHitung.Click
        nilai = TxtBilangan.text
        If nilai <= 0 Or nilai = 1 Then
            LblFaktorial.Text = 1
        ElseIf nilai > 1 Then
            For Me.faktorial = nilai - 1 To 1 Step -1
                nilai = nilai * faktorial
            Next faktorial
            LblFaktorial.Text = nilai
        End If

    End Sub

    Private Sub BtnHapus_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnHapus.Click
        TxtBilangan.Clear()
        LblFaktorial.Text = ""
        TxtBilangan.Focus()

    End Sub

    Private Sub BtnKeluar_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnKeluar.Click
        Me.Close()
    End Sub
End Class