ctype_alnum

说明

bool ctype_alnum ( string text )

Checks if all of the characters in the provided string, text, are alphanumeric. In the standard C locale letters are just [A-Za-z] and the function is equivalent to preg_match('/^[a-z0-9]+$/iD', $text).

参数

text: The tested string.

返回值

Returns TRUE if every character in text is either a letter or a digit, FALSE otherwise.

范例

例 1. A ctype_alnum() 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.\n";
    } else {
        echo "The string $testcase does not consist of all letters or digits.\n";
    }
}
?>

上例将输出：

The string AbCd1zyZ9 consists of all letters or digits.
The string foo!#$bar does not consist of all letters or digits.

add a note User Contributed Notes

Sinured
22-Jul-2007 05:13


Caution: ctype_alnum() will return false on integers.



<?php

var_dump(ctype_alnum('3')); // true

var_dump(ctype_alnum(3)); // false

?>



See http://bugs.php.net/bug.php?id=42007 .

raj
09-Jul-2007 11:54


When checking strings with multiple words for non alphanumeric characters ctype_alnum would consider space as non alphanumeric character as well. 



So to check a string with multiple words for non alphanumeric characters use str_replace



foreach ($imported_queries as $check_aplhanum) {

            $check_aplhanum = str_replace (" ", "", $check_aplhanum);

            if (!(ctype_alnum($check_aplhanum))) {

                echo "Query string contains alphanumeric characters";

            }

        }

add a note

ctype_alnum

说明

参数

返回值

范例

参见