Funzione VBScript che dato un indirizzo E-mail testa se è valido o meno.

If isValidEMail("IndirizzoE-Mail") Then
MsgBox("Indirizzo valido")
Else
MsgBox("Indirizzo non valido")
End If

function IsValidEmail(email)
isitvalid = true
dim names, name, i, c
names = Split(email, "@")
if UBound(names) <> 1 then
isitvalid = false
exit function
end if
for each name in names
if Len(name) <= 0 then
isitvalid = false
exit function
end if
for i = 1 to Len(name)
c = Lcase(Mid(name, i, 1))
if InStr("abcdefghijklmnopqrstuvwxyz_-.", c) <= 0 and not IsNumeric(c) then
isitvalid = false
exit function
end if
next
if Left(name, 1) = "." or Right(name, 1) = "." then
isitvalid = false
exit function
end if
next
if InStr(names(1), ".") <= 0 then
isitvalid = false
exit function
end if
i = Len(names(1)) - InStrRev(names(1), ".")
if i <> 2 and i <> 3 then
isitvalid = false
exit function
end if
if InStr(email, "..") > 0 then
isitvalid=false
Exit Function
end If
IsValidEmail = isitvalid
End Function