Public Function SostituisciStringa(s As String, s1 As String, _
   s2 As String) As String
'Autore: Lbo, Sandro
'esempio d'uso:
'Sostituiscistringa("pippoAAApippoAAApippo", "pippo", "pluto")
'restituisce: plutoAAAplutoAAApluto
    Dim start As Long
    Dim appo As String
    Dim appoLeft As String
    Dim appoRight As String
    Dim p As Long
    p = 1
    appo = s
    Do Until InStr(p, appo, s1) = 0
        p = InStr(p, appo, s1)
        If p > 1 Then
            appoLeft = Left(appo, (p - 1))
        Else
            appoLeft = ""
        End If
        appoRight = Right(appo, Len(appo) - (Len(appoLeft) + Len(s1)))
        appo = appoLeft & s2 & appoRight
        p = p + Len(s2)
    Loop
    SostituisciStringa = appo
End Function