ctype_xdigit

(PHP 4 >= 4.0.4, PHP 5)

ctype_xdigit --  Check for character(s) representing a hexadecimal digit

Description

bool ctype_xdigit ( string text)

Returns TRUE if every character in text is a hexadecimal 'digit', that is a decimal digit or a character from [A-Fa-f] , FALSE otherwise.

Example 1. A ctype_xdigit() example

<?php
$strings
= array('AB10BC99', 'AR1012', 'ab12bc99');
foreach (
$strings as $testcase) {
    if (
ctype_xdigit($testcase)) {
        echo
"The string $testcase consists of all hexadecimal digits.\n";
    } else {
        echo
"The string $testcase does not consist of all hexadecimal digits.\n";
    }
}
?>

This example will output :

The string AB10BC99 consists of all hexadecimal digits.
The string AR1012 does not consist of all hexadecimal digits.
The string ab12bc99 consists of all hexadecimal digits.

See also ctype_digit().