PHP 函数 ctype_punct()

<?php
   $strings = array('k211!@!$#', 'foo!#$bar', '*$()');

   foreach ($strings as $test) {
      if (ctype_punct($test)) {
         echo "$test consists of all punctuation. \n";
      }else {
         echo "$test does not have all punctuation. \n";
      }
   }
?>