Возвести число в степень

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim a As Integer = TextBox1.Text
        Dim n As Integer = TextBox2.Text
        Dim zarb As String = ""
        Dim zarb1 As String = a
        Dim zarb2 As String = ""
        Dim qm1 As Integer
        Dim adHq, adBq As Integer
        adHq = 0 : adBq = 0
        For i = 2 To n
            qm1 = 0 : zarb = 0 : zarb2 = "" : adBq = 0
            For j = zarb1.ToString.Length To 1 Step -1
                qm1 = Mid(zarb1, j, 1)
                zarb = (qm1 * a) + adBq
                If zarb.Length > 1 Then
                    adHq = Mid(zarb, zarb.ToString.Length, 1)
                    adBq = Mid(zarb, 1, zarb.ToString.Length - 1)
                Else
                    adHq = zarb
                    adBq = 0
                End If
                zarb2 = adHq & zarb2
                If j = 1 And adBq <> 0 Then zarb2 = adBq & zarb2
            Next
            zarb1 = zarb2
        Next
        MsgBox(zarb1)
    End Sub