检测表单输入EMAIL的合法性

function IsValidEmail(email)
dim names, name, i, c
'Check for valid syntax in an email address.
IsValidEmail = true 

names = Split(email, "@") 

if UBound(names) <> 1 then 

IsValidEmail = false 

exit function 

end if 

for each name in names 

if Len(name) <= 0 then 

IsValidEmail = 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 

IsValidEmail = false 

exit function 

end if 

next 

if Left(name, 1) = "." or Right(name, 1) = "." then 

IsValidEmail = false 

exit function 

end if 

next 

if InStr(names(1), ".") <= 0 then 

IsValidEmail = false 

exit function 

end if 

i = Len(names(1)) - InStrRev(names(1), ".") 

if i <> 2 and i <> 3 then 

IsValidEmail = false 

exit function 

end if 

if InStr(email, "..") > 0 then 

IsValidEmail = false 

end if
end function