NonDocumentTypeChildNode.previousElementSibling

previousElementSibling 返回当前元素在其父元素的子元素节点中的前一个元素节点,如果该元素已经是第一个元素节点,则返回null,该属性是只读的.

var prevNode = elementNodeReference.previousElementSibling;

<div id="div-01">Here is div-01</div>
<div id="div-02">Here is div-02</div>
<li>This is a list item</li>
<li>This is another list item</li>
<div id="div-03">Here is div-03</div>

<script type="text/javascript">
  var el = document.getElementById('div-03').previousElementSibling;
  document.write('<p>Siblings of div-03</p><ol>');
  while (el) {
    document.write('<li>' + el.nodeName + '</li>');
    el = el.previousElementSibling;
  }
  document.write('</ol>');
</script>

上面的例子会输出以下内容:

Siblings of div-03

   1. LI
   2. LI
   3. DIV
   4. DIV

Element Traversal Specification: previousElementSibling

• childElementCount
• children
• firstElementChild
• lastElementChild
• nextElementSibling