树状图

html部分：

<ul id="root">
    <li>
        <label><a>校讯通</a></label>
        <ul class="two">
            <li>
                <label><a>沈阳市</a></label>
                <ul class="two">
                    <li>
                        <label><a>二小</a></label>
                        <ul class="two">
                            <li>
                                <label><a>二年级</a></label>
                                <ul class="two">
                                    <li class="li"><label><a>2222222222</a></label></li>
                                    <li class="li"><label><a>3333333333</a></label></li>
                                    <li class="li"><label><a>4444444444</a></label></li>
                                </ul>
                            </li>
                            <li>
                                <label><a>三年级</a></label>
                                <ul class="two">
                                    <li>
                                        <label><a>一班</a></label>
                                        <ul class="two">
                                            <li class="li"><label><a>张三</a></label></li>
                                            <li>
                                                <label><a>王五</a></label>
                                                <ul class="two">
                                                    <li class="li"><label><a>班长</a></label></li>
                                                    <li class="li"><label><a>学习委员</a></label></li>
                                                </ul>
                                            </li>
                                        </ul>
                                    </li>
                                    <li><label><a>实验班</a></label></li>
                                </ul>
                            </li>
                        </ul>
                    </li>
                </ul>
            </li>
            <li>
                <label><a>抚顺市</a></label>
                <ul class="two">
                    <li class="li"><label><a>二小</a></label></li>
                    <li class="li"><label><a>一中</a></label></li>
                </ul>
            </li>
        </ul>
    </li>
</ul>

js部分：

<script type="text/javascript">
    $(function(){
        $(".li").click(function(){
            $(this).addClass("lan").siblings().removeClass("lan");
        })
    })
</script>
<script type="text/javascript" >
    var Tree = function(o){
        this.root = document.getElementById(o);
        this.labels = this.root.getElementsByTagName('label');
        var that = this;
        this.int();
        Tree.prototype.addEvent(this.root,'click',function(e){that.treeshow(e)});
    }
    Tree.prototype = {
        int:function(){//初始化页面，加载时给有孩子结点的元素动态添加图标
            for(var i=0;i<this.labels.length;i++){
                var span = document.createElement('span');
                span.style.cssText ='display:inline-block;height:18px;vertical-align:middle;16px;cursor:pointer;';
                span.innerHTML = ' '
                span.className = 'add';
                if(this.nextnode(this.labels[i].nextSibling)&&this.nextnode(this.labels[i].nextSibling).nodeName == 'UL')
                    this.labels[i].parentNode.insertBefore(span,this.labels[i]);
                else
                    this.labels[i].className = 'rem'
            }
        },
        treeshow:function(e){
            e = e||window.event;
            var target = e.target||e.srcElement;
            var tp = this.nextnode(target.parentNode.nextSibling);
            switch(target.nodeName){
                case 'A'://点击A标签展开和收缩树形目录，并改变其样式
                    if(tp&&tp.nodeName == 'UL'){
                        if(tp.style.display != 'block' ){
                            tp.style.display = 'block';
                            this.prevnode(target.parentNode.previousSibling).className = 'rem'
                        }else{
                            tp.style.display = 'none';
                            this.prevnode(target.parentNode.previousSibling).className = 'add'
                        }
                    }
                    break;
                case 'SPAN'://点击图标只展开或者收缩
                    var ap = this.nextnode(this.nextnode(target.nextSibling).nextSibling);
                    if(ap.style.display != 'block' ){
                        ap.style.display = 'block';
                        target.className = 'ren'
                    }else{
                        ap.style.display = 'none';
                        target.className = 'add'
                    }
                    break;
            }
        },
        addEvent:function(el,name,fn){//绑定事件
            if(el.addEventListener) return el.addEventListener(name,fn,false);
            return el.attachEvent('on'+name,fn);
        },
        nextnode:function(node){//寻找下一个兄弟并剔除空的文本节点
            if(!node)return ;
            if(node.nodeType == 1)
                return node;
            if(node.nextSibling)
                return this.nextnode(node.nextSibling);
        },
        prevnode:function(node){//寻找上一个兄弟并剔除空的文本节点
            if(!node)return ;
            if(node.nodeType == 1)
                return node;
            if(node.previousSibling)
                return prevnode(node.previousSibling);
        }
    }
    tree = new Tree("root");//实例化应用
</script>