ctype_xdigit

Description

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.

例子 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().