layui如何得到select值

nbsp;html&gt;  <meta>  <meta>  <title>增加、修改学校/层次/专业</title>  <link><div><form><br>          <div><h2>{$rs1.title} &gt;&gt; {$rs.title}</h2></div>          <div>            <label>学费</label>            <div>              <input>            </div>          </div>          <div>            <label>批次</label>            <div><select>                   <option>请选择批次</option>                  {volist name="batch_rs" id="batch"}    <option>{$batch.title}</option>    {/volist}</select>              </div>          </div>          <div>            <div>              <button>立即提交</button>            </div>          </div></form></div><script></script><script>layui.use([&#39;form&#39;, &#39;jquery&#39;], function(){  var form = layui.form  ,$= layui.$;  // var batch=$("#batch").val();   form.on(&#39;select&#39;, function(data){  console.log(data.elem); //得到select原始DOM对象  console.log(data.value); //得到被选中的值]  $("#batch").val(data.value)  console.log(data.othis); //得到美化后的DOM对象});       $(&#39;#editbatchschooltuition&#39;).on(&#39;click&#39;, function(){  var batch=$("#batch").val();  alert(batch);layer.ready(function(){   layer.open({type: 2,title: &#39;增加&#39;,maxmin: true,area: [&#39;750px&#39;, &#39;400px&#39;],content: &#39;{:url(&#39;main/addschool&#39;)}?id={$id}&price={$rs.price}&batch=&#39;+batch,//content: &#39;{:url(&#39;main/addschool&#39;)}&#39;,cancel: function(){ //刷新网页  }  });});});  });</script>