jQuery等待加载所有选择的选项

Question

我有一个选择框对象,ajax函数使用所选值作为输入调用OnChange.我还想在首次加载选择框时调用相同的函数.我使用jQuery .load,但是在加载任何选项之前调用了ajax函数,并且我的ajax函数的输入是未定义的.有没有人知道如何让jQuery在调用函数之前等待加载所有选项？

谢谢.

编辑 - 添加代码 我发现一个setTimeout()可以很好地延迟功能.但是,我使用起来很紧张,setTimeout()因为如果页面加载速度比平时慢,则无法正常工作.我尝试$(document).ready按照您的建议替换超时,但在选择选项并且输入未定义之前仍然调用该函数.

这是代码:

<script type="text/JavaScript">    
    setTimeout('AjaxFunction($("#SelectID option:selected").val()));', 400);
</script>

<select id="SelectID" name="SelectName" onchange="AjaxFunction(this.value);">
<option value='Inland Empire'>Inland Empire</option>
<option value='San Bernardino'>San Bernardino</option>  
<option value='Riverside'>Riverside</option>
<option value='California'>California</option>  
</select>

Answer 1

您应该考虑删除onchange=并使用以下方法之一来绑定事件/执行它:

<select id="SelectID" name="SelectName">
  <option value='Inland Empire'>Inland Empire</option>
  <option value='San Bernardino'>San Bernardino</option>  
  <option value='Riverside'>Riverside</option>
  <option value='California'>California</option>  
</select>

<script type="text/JavaScript">
    // placing the script after the select SHOULD ensure it executes after the 
    // select has been created
    $("#SelectID").change(function() {  // bind a change event:
      AjaxFunction($(this).val());
    }).change(); // and trigger a "change" event immediately

    // If you are using .load to bring #SelectID into existence, 
    // it would be much better to put the whole segment into the callback of
    // .load() as suggested by gaby

    $("#sometarget").load("/some-url-with-select-box", function() {
      // bind and trigger change event (alternate forms)
      $("#SelectID").bind('change', function() {
        AjaxFunction($(this).val());
      }).trigger('change');    
    });
</script>

Answer 2

你能展示一些迄今为止的代码吗？使用jQuery的ready()函数应该可以实现你想要的.它基本上等待整个DOM在执行之前加载.

 $(document).ready(function(){
    //code here runs after the DOM is created
 });