PHP Tutorial : Ctype character type checking

Happy 1st June for those under 18

Yesterday I’ve found a nice function in php called ctype. And? What it does? Well, I see it as a replacement for regular expressions. PHP Ctype function checks for character type. Let’s hear the chars type we can check with that nice function  :

• alphanumeric characters – ctype_alnum()
• alphabetic characters      – ctype_alpha()
• control characters           – ctype_cntrl()
• numeric characters         – ctype_digit()
• lowercase characters      – ctype_lower()
• uppercase characters      – ctype_upper()
• printable characters        – ctype_print()
• any printable character but not whitespace or an alphanumeric – ctype_punct()
• any printable characters but not space – ctype_graph()
• whitespace characters    – ctype_space()
• hexadecimal digit characters – ctype_xdigit()

Ok, long list huh? but usefull. I will show you a simple example which of course can be applied for all other ctype() functions :

<?php
//will check if a character type is digit

$toCheck = 1010;

if(ctype_digit($toCheck)) {

print "$toCheck is a number";
}else{

print "$toCheck is NOT a number";
}
?>