built in function to do custom checks on int or floats

built in function to do custom checks on int or floats


not sure if this is built in or not, but all i need to do is check if
an input text value is a Int, Float and contain less than x amount of
characters. I read the API and not sure if it's already built in or
i'll have to add it.
If i have to add it myself where is a good tutorial?