问先获取高度ul

EN

<div class="container">
  <h5>First one has height of 40px</h5>
  <ul style="height:40px">
    <li>Test</li>
    <li>Test1</li>
  </ul>

  <h5>Second one has height of 70px</h5>
  <ul style="height:70px">
    <li>Test</li>
    <li>Test1</li>
    <li>Test2</li>
    <li>Test3</li>
  </ul>
</div>
<button id="submit">Get height</button>

$( "#submit" ).click(function() {

    /* Replace .container with ur this selector */
  var height = $('.container').find("ul").filter(":first").height();

  alert(height);
});