Question

这是我的代码：

<body>
  <div id="players" style="display:block">
    22
  </div>
  <select class="form-control playerDD" style="font-weight: normal" name="player_1" id="player_1">
    <option value="default">Select a player</option>
    <optgroup label="Available Players">
      <option value="22">John Smith</option>
      <option value="23">Jane Smith</option>
      <option value="24">Sam Smith</option>
    </optgroup>
    <optgroup label="Unavailable Players">
      <option value="25">John Smith 2</option>
      <option value="26">Jane Smith 2</option>
      <option value="27">Sam Smith 2</option>
    </optgroup>
  </select>

  <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
  <script>
    var foo = $("#players").text();
    alert(foo);                       // Getting the right value and type
    //foo = "22";                     // This will work! 
    $("#player_1").val(foo);          // Does not work
    alert($('#player_1').val());      // Getting null
  </script>
</body>

问题：我正在尝试根据div（id：players）中的值设置下拉列表（id：player_1）的值。我能够正确读取值但无法设置它。在JavaScript中，如果我硬编码foo的值，它就可以了！

这是jsfiddle：https://jsfiddle.net/4w1ack9f/2/

Answer 1

$( document ).ready(function() {
    $('#player_1').val(parseInt($('#players').text()));
});

使用jQuery设置select by选项值

1 个答案: