PHP 函数 ctype_graph() PHP 函数 ctype_digit() PHP 函数 ctype_lower() PHP 函数 ctype_graph() <?php $strings = array('asdf\n\r\t', 'arf12', 'LKA#@%.54'); foreach ($strings as $test) { if (ctype_graph($test)) { echo "$test consists of all (visibly) printable characters \n"; }else { echo "$test does not have all (visibly) printable characters. \n"; } } ?> PHP 函数 ctype_digit() PHP 函数 ctype_lower()