ctype_alpha

(PHP 4 >= 4.0.4)

ctype_alpha -- Check for alphabetic character(s)

Description

bool ctype_alpha ( string text)

Returns TRUE if every character in text is a letter from the current locale, FALSE otherwise. In the standard C locale letters are just [A-Za-z] and ctype_alpha() is equivalent to (ctype_upper($text) || ctype_lower($text)) if $text is just a single character, but other languages have letters that are considered neither upper nor lower case.

例子 1. A ctype_alpha() example (using the default locale)

<?php
$strings
= array('KjgWZC', 'arf12');
foreach (
$strings as $testcase) {
    if (
ctype_alpha($testcase)) {
        echo
"The string $testcase consists of all letters.\n";
    } else {
        echo
"The string $testcase does not consist of all letters.\n";
    }
}
?>

This example will output :

The string KjgWZC consists of all letters.
The string arf12 does not consists of all letters.

See also ctype_upper(), ctype_lower(), and setlocale().