Determine if an integer is not in a list

With UDF

Option Explicit

Function CheckNb(ByVal MyNb As Integer, MyList) As Boolean
Const Ch = ","
Dim MyCh
    MyCh = Ch & MyNb & Ch
    MyList = Ch & MyList & Ch
    CheckNb = True
    If (Len(MyList) <> Len(Replace(MyList, MyCh, ""))) Then CheckNb = False
End Function