ctype_digit

(PHP 4 >= 4.0.4, PHP 5)

ctype_digit -- Check for numeric character(s)

Description

bool ctype_digit ( string text)

Returns TRUE if every character in text is a decimal digit, FALSE otherwise.

例子 1. A ctype_digit() example

<?php
$strings
= array('1820.20', '10002', 'wsl!12');
foreach (
$strings as $testcase) {
    if (
ctype_digit($testcase)) {
        echo
"The string $testcase consists of all digits.\n";
    } else {
        echo
"The string $testcase does not consist of all digits.\n";
    }
}
?>

This example will output :

The string 1820.20 does not consists of all digits.
The string 10002 consists of all digits.
The string wsl!12 does not consists of all digits.

See also ctype_alnum() and ctype_xdigit().