Example 1. A ctype_lower() example (using the default locale)
<?php $strings = array('aac123', 'qiutoas', 'QASsdks'); foreach ($strings as $testcase) {     if (ctype_lower($testcase)) {         echo "The string $testcase consists of all lowercase letters.\n";     } else {         echo "The string $testcase does not consist of all lowercase letters.\n";     } } ?>
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The above example will output:
The string aac123 does not consist of all lowercase letters.
The string qiutoas consists of all lowercase letters.
The string QASsdks does not consist of all lowercase letters.  |