javascript - 组合框 jquery onchange 事件

Question

我如何根据另一个组合框更新组合框，我有这段代码，但它不起作用，有人可以帮助我。谢谢

  <select name="marca" id="marca" onchange="javascript:carregaModelos(this.value)" >
    <option th:each="marca : ${marcas}" 
      th:value="${marca.idmarca}" 
      th:text="${marca.nomemarca}">Marca</option>
</select>

     <select   name="modelo" id="modelo">
  <option th:each="modelo : ${modelos}" 
      th:value="${idmodelo}" 
      th:text="${nomemodelo}">Modelo</option>
     </select>


<script type="text/javascript">     
   function carregaModelos(marca) { 
 var opcao = $(this).('#marca option')   
 console.log(opcao);
 jQuery("#modelo").load( "pesquisa/" + opcao);
 return false;


}

还有这个

 @RequestMapping("/pesquisa/{idmarca}")
    public String pesquisa(ModelMap model, @PathVariable Long idmarca) {
        model.addAttribute("modelo", service.obterModelosByMarcas(idmarca));
        return "index";

Answer 1

向目标元素添加具有值的属性。

data-target-sync="#targetElementId"

The value is jQuery selector so # included with ID of target element

$(document).ready(function() {

  $('[data-target-sync]').change(function() {

    var cur = $(this);

    $(cur.attr('data-target-sync')).val(cur.val());

  });

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<select name="marca" id="marca" data-target-sync="#modelo">
  <option value="a">A</option>
  <option value="b">B</option>
  <option value="c">C</option>


</select>

<select name="modelo" data-target-sync="#marca" id="modelo">
  <option value="a">A</option>
  <option value="b">B</option>
  <option value="c">C</option>

</select>