Element.lastElementChild

只读属性 ParentNode.lastElementChild 返回对象的最后一个子元素，如果没有子元素，则返回 null。

This property was initially defined in the ElementTraversal pure interface. As this interface contained two distinct set of properties, one aimed at Node that have children, one at those that are children, they have been moved into two separate pure interfaces, ParentNode and ChildNode. In this case, lastElementChild moved to ParentNode. This is a fairly technical change that shouldn't affect compatibility.

语法

var element = node.lastElementChild;

例子

<ul id="foo">
  <li>First  (1)</li>
  <li>Second (2)</li>
  <li>Third  (3)</li>
</ul>

<script>
var foo = document.getElementById('foo');
// yields: Third  (3)
console.log(foo.lastElementChild.textContent);
</script>

适用于 IE8、IE9 和 Safari 的 Polyfill

// Overwrites native 'lastElementChild' prototype.
// Adds Document & DocumentFragment support for IE9 & Safari.
// Returns array instead of HTMLCollection.
;(function(constructor) {
    if (constructor &&
        constructor.prototype &&
        constructor.prototype.lastElementChild == null) {
        Object.defineProperty(constructor.prototype, 'lastElementChild', {
            get: function() {
                var node, nodes = this.childNodes, i = nodes.length - 1;
                while (node = nodes[i--]) {
                    if (node.nodeType === 1) {
                        return node;
                    }
                }
                return null;
            }
        });
    }
})(window.Node || window.Element);

规范

规范 状态 备注
DOM
ParentNode.lastElementChild		 Living Standard Splitted the ElementTraversal interface in ChildNode and ParentNode. This method is now defined on the latter.
The Document and DocumentFragment implemented the new interfaces.
Element Traversal Specification
ElementTraversal.lastElementChild		 Obsolete Added its initial definition to the ElementTraversal pure interface and use it on Element.

参见