nextSibling和previousSibling

  在FireFox中包含众多空格作为文本节点,因此在我们使用nextSibling和previousSibling时就会出现问题。因为FireFox会把文本节点误当做元素节点的兄弟节点来处理。我们可以添加nodeType来判断。当上一节点或者是下一节点为文本节点时,就继续寻找,直到找到下一个元素节点。以下代码仅供参考,在fireFox中测试通过:

        //下一个兄弟节点
        function nextSibling(node) {
            var tempLast = node.parentNode.lastChild;
            if (node == tempLast) return null;
            var tempObj = node.nextSibling;
            while (tempObj.nodeType != 1 && tempObj.nextSibling != null) {
                tempObj = tempObj.nextSibling;
            }
            return (tempObj.nodeType==1)? tempObj:null;
        }
        //前一个兄弟节点
        function prevSibling(node) {
            var tempFirst = node.parentNode.firstChild;
            if (node == tempFirst) return null;
            var tempObj = node.previousSibling;
            while (tempObj.nodeType != 1 && tempObj.previousSibling != null) {
                tempObj = tempObj.previousSibling;
            }
            return (tempObj.nodeType==1)? tempObj:null;
        }    
测试代码
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
    <script type="text/javascript" language="javascript" >
        window.onload = function () {
            var oUl = document.getElementsByTagName("UL");
            var nodeLi = oUl[0].childNodes[3];

            var nextListItem = nodeLi.nextSibling;
            var preListItem = nodeLi.previousSibling;

            alert(nextListItem.tagName + " " + preListItem.tagName);

            nextListItem = nextSibling(nodeLi);
            preListItem = prevSibling(nodeLi);

            alert(nextListItem.tagName + " " + preListItem.tagName);
           
        }

        //下一个兄弟节点
        function nextSibling(node) {
            var tempLast = node.parentNode.lastChild;
            if (node == tempLast) return null;
            var tempObj = node.nextSibling;
            while (tempObj.nodeType != 1 && tempObj.nextSibling != null) {
                tempObj = tempObj.nextSibling;
            }
            return (tempObj.nodeType==1)? tempObj:null;
        }
        //前一个兄弟节点
        function prevSibling(node) {
            var tempFirst = node.parentNode.firstChild;
            if (node == tempFirst) return null;
            var tempObj = node.previousSibling;
            while (tempObj.nodeType != 1 && tempObj.previousSibling != null) {
                tempObj = tempObj.previousSibling;
            }
            return (tempObj.nodeType==1)? tempObj:null;
        }    

    </script>
    
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <ul>
            <li>HTML</li>
            <li>CSS</li>
            <li>JavaScript</li>
            <li>JQuery</li>
            <li>Dom</li>
        </ul>
        <ul>
            <li>ASP.NET</li>
            <li>JSP</li>
            <li>PHP</li>
            <li>VB.NET</li>
        </ul>
    </div>
    </form>
</body>
</html>

其中nodeType的值主要有以下几种:

  1. 元素节点的nodeType值为1
  2. 属性节点的nodeType值为2
  3. 文本节点的nodeType值为3
posted @ 2012-04-19 11:45  scogee  阅读(10692)  评论(0编辑  收藏  举报