Changing Number Format Based On Value Of Another Cell

[HarryT]

I am trying to set the number of decimal places in cell B3 when cell A1 is changed. If the number 2 is in A1 then I want 2 decimal places in B3, if A1 is 3 then I want 3 decimal places. These are the only two options I need at this point.

I need the code to auto run each time cell A1 is updated.

Any help is appreciated.

Thanks.

 

[Scott Huish]

Perhaps:

Private Sub Worksheet_Change(ByVal Target As Range)
Dim t As Integer
If Intersect(Target, Range("A1")) Is Nothing Then Exit Sub
If Application.WorksheetFunction.IsNumber(Range("A1")) Then
    t = Int(Range("A1"))
    If t > 0 And t < 3 Then Range("B3").NumberFormat = "#." & String(t, "0")
End If
End Sub