The functions provided by this extension check whether a character or string falls into a certain character class according to the current locale (see also setlocale()).
When called with an integer argument these functions behave exactly like their C counterparts from "ctype.h".
When called with a string argument they will check every character in the string and will only return TRUE if every character in the string matches the requested criteria.
Passing anything else but a string or integer will return FALSE immediately.
None besides functions from the standard C library which are always available.
Beginning with PHP 4.2.0 these functions are enabled by default. For older versions you have to configure and compile PHP with --enable-ctype.
This extension does not define any configuration directives.
This extension does not define any resource types.
This extension does not define any constants.