comment indicer une textbox ?

Dans la tentative ci-dessous j'essaye de creer des textbox en série en créant un groupe....
Dim n As Integer
Dim s As String
Dim gb As New groupbox
Dim tb1 As New TextBox
Dim tb2 As New TextBox
Dim tb3 As New TextBox
Dim tb4 As New TextBox
Dim tb5 As New TextBox
Dim tb6 As New TextBox
For n = 1 To 6
s = String.Format("tb{0}", n)
gb.Controls.Add(s)
s = String.Format("tb{0}.top", n)
s = n * 20
Next n
Controls.Add(gb)
....avez vous une solution similaire , mais qui marche ?

temp.Size = New System.Drawing.Size(24, 24)
Dim o As Integer
For m As Integer = 0 To 4
For n As Integer = 0 To 9
tb(n, m) = temp
Me.Controls.Add(tb(n, m))
Me.tb(n, m).Top = 25 * n
Me.tb(n, m).Left = 25 * m
Me.tb(n, m).Text = Str(n + (m * 10))
Next n
Next m