我有一個 html 表單，我需要使用 enter 鍵從輸入切換焦點（感謝我的主管說大多數人不知道 tab 鍵的用途）我已經嘗試過這個解決方案<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js">jQuery.extend(jQuery.expr[':'], {    focusable: function (el, index, selector) {            return $(el).is('a, button, :input, [tabindex]');    }    });$(document).on('keydown', 'focusable', function (e) {        if (e.which == 13) {            e.preventDefault();            var $canfocus = $(':focusable');            var index = $canfocus.index(this) + 1;            if (index >= $canfocus.length) index = 0;            $canfocus.eq(index).focus();    }    });    </script>這是我的表格<form method = "post" action = "<?php echo htmlspecialchars($_SERVER['PHP_SELF'])?>">        <label for = "maquina">Maquina:</label><span class = "error"> * <?php echo $maquinaErr;?></span><br>        <input type = "number" id = "maquina" name = "maquina" size = "20" tabindex = "1" value = "<?php echo $maquina;?>" autofocus><br><br>        <label for = "gafete">Numero de gafete:</label><span class = "error" id = "eGafete"> * <?php echo $gafeteErr;?></span><br>        <input type = "number" id = "gafete" name = "gafete" size = "20" tabindex = "2" value = "<?php echo $gafete;?>" onchange = "llamarGafete()">        <br><br>        <label for = "nparte">Numero de parte del componente:</label><span class = "error" id = "eNparte"> * <?php echo $nparteErr;?></span><br>        <input type = "number" id = "nparte" name = "nparte" size = "20" tabindex = "3" value = "<?php echo $nparte;?>" onchange = "llenarUM()"><br><br>        <label for = "um">UM:</label><span class = "error"> * <?php echo $umErr;?></span><br>        <input type = "text" id = "um1" name = "um" size = "20" tabindex = "-1" value = "<?php echo $um;?>" readonly><br><br>    </form>