CTYPE_ALNUM(3) 1 CTYPE_ALNUM(3) ctype_alnum - Check for alphanumeric character(s) SYNOPSIS bool ctype_alnum (string $text) DESCRIPTION Checks if all of the characters in the provided string, $text, are alphanumeric. PARAMETERS o $text - The tested string. RETURN VALUES Returns TRUE if every character in $text is either a letter or a digit, FALSE otherwise. EXAMPLES Example #1 A ctype_alnum(3) example (using the default locale) <?php $strings = array('AbCd1zyZ9', 'foo!#$bar'); foreach ($strings as $testcase) { if (ctype_alnum($testcase)) { echo "The string $testcase consists of all letters or digits. "; } else { echo "The string $testcase does not consist of all letters or digits. "; } } ?> The above example will output: The string AbCd1zyZ9 consists of all letters or digits. The string foo!#$bar does not consist of all letters or digits. NOTES Note If an integer between -128 and 255 inclusive is provided, it is interpreted as the ASCII value of a single character (negative val- ues have 256 added in order to allow characters in the Extended ASCII range). Any other integer is interpreted as a string contain- ing the decimal digits of the integer. SEE ALSO ctype_alpha(3), ctype_digit(3), setlocale(3). PHP Documentation Group CTYPE_ALNUM(3)