下面是SimpleTree 的JS代码
/*

• jQuery SimpleTree Drag&Drop plugin
• Update on 22th May 2008
• Version 0.3 *
• Licensed under BSD http://en.wikipedia.org/wiki/BSD_License
• Copyright (c) 2008, Peter Panov panov@elcat.kg, IKEEN Group http://www.ikeen.com
• All rights reserved. *
• Redistribution and use in source and binary forms, with or without
• modification, are permitted provided that the following conditions are met:
• * Redistributions of source code must retain the above copyright
• notice, this list of conditions and the following disclaimer.
• * Redistributions in binary form must reproduce the above copyright
• notice, this list of conditions and the following disclaimer in the
• documentation and/or other materials provided with the distribution.
• * Neither the name of the Peter Panov, IKEEN Group nor the
• names of its contributors may be used to endorse or promote products
• derived from this software without specific prior written permission. *
• THIS SOFTWARE IS PROVIDED BY Peter Panov, IKEEN Group ``AS IS'' AND ANY
• EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
• WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
• DISCLAIMED. IN NO EVENT SHALL Peter Panov, IKEEN Group BE LIABLE FOR ANY
• DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
• (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
• LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
• ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
• (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
• SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */

$.fn.simpleTrees = function(opt){
return this.each(function(){
var TREE = this;
var ROOT = $('.root',this);
var mousePressed = false;
var mouseMoved = false;
var dragMoveType = false;
var dragNode_destination = false;
var dragNode_source = false;
var dragDropTimer = false;
var ajaxCache = Array();

    var beforeAjax = false;
    var nodeCheckBox = false;
    var checkBoxClick = false;
    var return_state = false;

    TREE.option = {
        drag:       false,
        animate:    false,
        autoclose:  false,
        speed:      'fast',
        afterAjax:  false,
        afterMove:  false,
        afterClick: false,
        afterDblClick:  false,
        afterContextMenu:   false,
        docToFolderConvert:false,
        beforeAjax : false, //beforeAjax : 展开AJAX之前事件

        /**
         * 复选框属性及状态标志
         * 默认属性，支持重新定义
         * by zhengchao 2010-04-05
         * 例： <span ck='a'>表示全选</span>
         */
        nodeCheckBox : false,
        ckFlag : 'ck',          //标签中的元素
        allCheckFlag  : 'a',    //全选
        halfCheckFlag : 'h',    //半选
        noCheckFlag   : 'n',    //没选
        checkBoxClick : false,   //多选框事件
        hasIcon: true,      //是否显示节点图标
        pnode : ''
    };

    TREE.option = $.extend(TREE.option,opt);
    $.extend(this, {getSelected: function(){
        return $('span.active', this).parent();
    }});
    TREE.closeNearby = function(obj)
    {
        $(obj).siblings().filter('.folder-open, .folder-open-last, .folder-noicon-open').each(function(){
            var childUl = $('>ul',this);
            var className = this.className;
            this.className = className.replace('open','close');
            if(TREE.option.animate)
            {
                childUl.animate({height:"toggle"},TREE.option.speed);
            }else{
                childUl.hide();
            }
        });
    };
    TREE.nodeToggle = function(obj)
    {
        var childUl = $('>ul',obj);
        if(childUl.is(':visible')){
            obj.className = obj.className.replace('open','close');

            if(TREE.option.animate)
            {
                childUl.animate({height:"toggle"},TREE.option.speed);
            }else{
                childUl.hide();
            }
        }else{
            obj.className = obj.className.replace('close','open');
            if(TREE.option.animate)
            {
                childUl.animate({height:"toggle"},TREE.option.speed, function(){
                    if(TREE.option.autoclose)TREE.closeNearby(obj);
                    if(childUl.is('.ajax'))TREE.setAjaxNodes(childUl, obj.id);
                });
            }else{
                childUl.show();
                if(TREE.option.autoclose)TREE.closeNearby(obj);
                if(childUl.is('.ajax'))TREE.setAjaxNodes(childUl, obj.id);
            }
        }
    };
    TREE.setAjaxNodes = function(node, parentId, callback)
    {
        if($.inArray(parentId,ajaxCache) == -1){
            ajaxCache[ajaxCache.length]=parentId;
            var url = $.trim($('>li', node).text());
            if(url && url.indexOf('url:'))
            {
                url=$.trim(url.replace(/.*\{url:(.*)\}/i ,'$1'));
                $.ajax({
                    type: "POST",
                    url: url,
                    contentType:'html',
                    cache:false,
                    success: function(responce){
                        //AJAX节点展开前动作
                        if (typeof TREE.option.beforeAjax == 'function'){
                            TREE.option.beforeAjax(node);
                        }
                        node.removeAttr('class');
                        node.html(responce);
                        $.extend(node,{url:url});
                        TREE.setTreeNodes(node, false); //true or false
                        if(typeof TREE.option.afterAjax == 'function')
                        {
                            TREE.option.afterAjax(node);
                        }
                        if(typeof callback == 'function')
                        {
                            if(return_state ==false){

                                callback(node);
                            }
                        }
                    }
                });
            }

        }
    };
    TREE.setTreeNodes = function(obj, useParent){
        obj = useParent? obj.parent():obj;
        var nodes_ = [];
        nodes_ = $('li>span', obj);

        nodes_.addClass('text');
        nodes_.bind('selectstart', function(){return false;});
        nodes_.click(function(){
            $('.active',TREE).attr('class','text');
            if(this.className=='text')
            {
                this.className='active';
            }
            if(typeof TREE.option.afterClick == 'function')
            {
                TREE.option.afterClick($(this).parent());
            }
            return false;
        });
        nodes_.dblclick(function(){
            mousePressed = false;
            TREE.nodeToggle($(this).parent().get(0));
            if(typeof TREE.option.afterDblClick == 'function')
            {
                TREE.option.afterDblClick($(this).parent());
            }
            return false;
        });
        nodes_.bind("contextmenu",function(){
            $('.active',TREE).attr('class','text');
            if(this.className=='text')
            {
                this.className='active';
            }
            if(typeof TREE.option.afterContextMenu == 'function')
            {
                TREE.option.afterContextMenu($(this).parent());
            }
            return false;
        });
        nodes_.mousedown(function(event){
            mousePressed = true;
            cloneNode = $(this).parent().clone();
            var LI = $(this).parent();
            if(TREE.option.drag)
            {
                $('>ul', cloneNode).hide();
                $('body').append('<div id="drag_container"><ul></ul></div>');
                $('#drag_container').hide().css({opacity:'0.8'});
                $('#drag_container >ul').append(cloneNode);
                $("<img>").attr({id : "tree_plus",src   : "../images/plus.gif"}).css({width: "7px",display: "block",position: "absolute",left   : "5px",top: "5px", display:'none'}).appendTo("body");
                $(document).bind("mousemove", {LI:LI}, TREE.dragStart).bind("mouseup",TREE.dragEnd);
            }
            return false;
        });
        nodes_.mouseup(function(){
            if(mousePressed && mouseMoved && dragNode_source)
            {
                TREE.moveNodeToFolder($(this).parent());
            }
            TREE.eventDestroy();
        });
        /**
         * 生长出多选框
         * @author zhengchao
         */
        if(TREE.option.nodeCheckBox){
            var parentChecked_ = 0 ; // 全选框默认 undefined状态
            var parentIndeterminate_ = 0; //半选框默认 undefined状态

            if($("input:first",obj.parent()).prop("checked")){
                parentChecked_ = 2; //全选
            }else {
                parentChecked_ = 1; //没选
            }

            if($("input:first",obj.parent()).attr("indeter")=='true' || $("input:first",obj.parent()).attr("indeter")==true){
                parentIndeterminate_ = 2; //半选
            }else {
                parentIndeterminate_ = 1; //没选
            }

            nodes_.each(function (){//alert($(this).attr("checked"));
                //纯净标签

                if(this.getAttribute('checked') == '1'){//2011-6-14 luke
                    // console.log('checked');
                    var nodeHtml = "<input type='image' src='../images/tree/iconCheckAll.gif' checked indeter='false' name='tree_chk' class='tree_chk' id='tree_chk' value='"+$(this).attr("value")+"'/>";//"<input type='checkbox' name='tree_chk' onclick='event.cancelBubble=true;' />";
                }else{
                    // console.log('unchecked');
                    var nodeHtml = "<input type='image' src='../images/tree/iconUnCheckAll.gif' indeter='false' name='tree_chk' class='tree_chk' id='tree_chk' value='"+$(this).attr("value")+"'/>";//"<input type='checkbox' name='tree_chk' onclick='event.cancelBubble=true;' />";
                }
                nodeHtml += $(this).html();
                $(this).html(nodeHtml);
                var input_ = $("input[type=image]",$(this)).eq(0);
                //如果父节点全选，则将所有下级子节点全选
                if(parentChecked_ == 2)$(this).attr(TREE.option.ckFlag,TREE.option.allCheckFlag);
                if(parentChecked_ == 1 && parentIndeterminate_ == 1)$(this).attr(TREE.option.ckFlag,TREE.option.noCheckFlag);

                if(this.getAttribute('checked') == '1'){//2011-6-14 luke
                    TREE.checkBoxStatus(input_,false,true);
                }else{
                    TREE.checkBoxStatus(input_,false,false);
                }
                //状态构造
        /**     if($(this).attr(TREE.option.ckFlag) == undefined || //没有设置标志，默认认为没选
                    $(this).attr(TREE.option.ckFlag) == TREE.option.noCheckFlag){//没选
                    $(this).attr(TREE.option.ckFlag,TREE.option.noCheckFlag);//修正 undefined 设置
                    TREE.checkBoxStatus(input_,false,false);
                }else if($(this).attr(TREE.option.ckFlag) == TREE.option.halfCheckFlag){//半选
                    TREE.checkBoxStatus(input_,true,false);
                }else if($(this).attr(TREE.option.ckFlag) == TREE.option.allCheckFlag){//全选
                    TREE.checkBoxStatus(input_,false,true);
                }**/
                if(typeof TREE.option.checkBoxClick == 'function'){//如果事件被重写，则利用重写的事件规则
                    TREE.option.checkBoxClick(input_);
                }else{// 否则为复选框绑定默认事件规则
                    input_.click(function (e){TREE.checkBoxClickDefault(input_);});
                }
                TREE.changeParentNodes(input_);//2011-6-14 luke
            });
        }

        //针对li进行操作
        var li_ = [];
        li_ = $('li', obj);
        li_.each(function(i){
            var nodeId = "";
            if(this.attributes[0] != undefined){
                 nodeId= this.attributes[0].value;
            }
            var className = this.className;
            var open = false;
            var cloneNode = false;
            var LI = this;
            var childNode = $('>ul',this); //当前li的子集
            if(childNode.size()>0){//如果存在子集
                var setClassName = 'folder-';
                if(className && className.indexOf('open')>=0){ //判断子集状态
                        setClassName=setClassName+'open';
                        open = true;
                }else{
                        setClassName=setClassName+'close';
                }
                //判断是否是末节点，给予 -last样式
                if(TREE.option.hasIcon==true){
                    this.className = setClassName + ($(this).is(':last-child')? '-last':'');
                }else{
                    this.className = "folder-noicon-close";
                }
                //子集未打开或者为AJAX节点，隐藏子集
                if(!open || className.indexOf('ajax')>=0)childNode.hide();

                TREE.setTrigger(this);
            }else{
                TREE.setTrigger(this);
                var setClassName = 'doc';
                this.className = setClassName + ($(this).is(':last-child')? '-last':'');
            }
            if(nodeId == TREE.option.pnode){
                return_state= true;
            }
        });
        li_.before('<li class="line">&nbsp;</li>');
        li_.filter(':last-child').after('<li class="line-last"></li>');

        TREE.setEventLine($('.line, .line-last', obj));
    };

    // 复选框状态控制 by zhengchao
    TREE.checkBoxStatus = function(inputCheck,indeterminate,checked){
        //判断类型，这里必须是BOOLEAN类型
        if(typeof(indeterminate)=="boolean" && typeof(checked)=="boolean"){
    $(inputCheck).prop("checked",checked);
            $(inputCheck).attr("indeter",checked.toString());
            if(checked==true){
                $(inputCheck).attr("src","../images/tree/iconCheckAll.gif");
            //  $(inputCheck).attr("checked","2");
            }else{
                if(indeterminate==true){
                    $(inputCheck).attr("src","../images/tree/iconCheckGray.gif");
            //      $(inputCheck).attr("checked","1");
                }else{
                    $(inputCheck).attr("src","../images/tree/iconUnCheckAll.gif");
            //      $(inputCheck).attr("checked","0");
                }
            }

        }else{
            //alert("出现参数类型异常jquery.simple.tree.js");
        }
    };

    // 复选框默认事件 by zhengchao
    TREE.checkBoxClickDefault = function(input){//alert($(input).attr("checked"));
        if(!$(input).prop("checked")){//如果选中
            $("input[type=image]",$(input).parent().parent()).each(function (index){
                TREE.checkBoxStatus(this,false,true);
            });
        }else{//没选中
            $("input[type=image]",$(input).parent().parent()).each(function (index){
                TREE.checkBoxStatus(this,false,false);
            });
        }
        TREE.changeParentNodes($(input));
    };

    /**
     * 改变父节点状态(递归)
     * @param {} node
     * by zhengchao
     */
    TREE.changeParentNodes = function(input){
        var input_ = $(input).parent().parent().parent().parent();
        //根据根节点没有复选框的要求，来跳出当前递归
        //alert($("span:first",$(input_)).eq(0).html().indexOf("input"));
        //if($("span:first",$(input_)).eq(0).html().indexOf("INPUT")== -1) return ;
        if($("span:first",$(input_)).eq(0).html().indexOf("input")== -1 && $("span:first",$(input_)).eq(0).html().indexOf("INPUT")== -1) return ;
        var parentInput = $("input:first",$(input_)).eq(0);//找到父节点的选择框
        var callbackValue = TREE.decideBrotherChecked(input) ; //搜捕同级兄弟节点状态
        //父节点状态
        //alert(parentInput+"==="+callbackValue);
        if(callbackValue==2){
            TREE.checkBoxStatus(parentInput,false,true);
        }else if(callbackValue==1){
            TREE.checkBoxStatus(parentInput,true,false);
        }else if(callbackValue==0){
            TREE.checkBoxStatus(parentInput,false,false);
        }
        TREE.changeParentNodes($(parentInput));
    };

    /**
     * 判断同级节点状态
     * return ：
     *      全选上了： 2
     *      半选上了： 1
     *      都没选上： 0
     * @author zhengchao
     */
    TREE.decideBrotherChecked = function (input){
        var nowThis = $(input).parent().parent().parent();
        var flagInteger = 0 ; //返回值变量
        var temp_ = 0; //临时变量
        var countBrother = $("input[type=image]" ,nowThis).size();//同级兄弟节点数
        $("input[type=image]" ,nowThis).each(function (index){
            if(this.checked) temp_++;//选中
            if(this.indeter){//发现半选，直接判定结果，并跳出循环
                flagInteger = 1;
                return false ;
            }
        });
        if(flagInteger != 1){
            if(temp_ == 0) return 0;
            if(temp_ != countBrother) return 1;
            if(temp_ == countBrother) return 2;
        }
        return flagInteger;
    }


    TREE.setTrigger = function(node){
        $('>span',node).before('<img class="trigger" src="../images/spacer.gif" border=0 />');
        var trigger = $('>.trigger', node);
        TREE.nodeToggle(node);
        trigger.click(function(event){
            TREE.nodeToggle(node);
        });
        if(!$.browser.msie)
        {
            trigger.css('float','left');
        }
    };
    TREE.dragStart = function(event){
        var LI = $(event.data.LI);
        if(mousePressed)
        {
            mouseMoved = true;
            if(dragDropTimer) clearTimeout(dragDropTimer);
            if($('#drag_container:not(:visible)')){
                $('#drag_container').show();
                LI.prev('.line').hide();
                dragNode_source = LI;
            }
            $('#drag_container').css({position:'absolute', "left" : (event.pageX + 5), "top": (event.pageY + 15) });
            if(LI.is(':visible'))LI.hide();
            var temp_move = false;
            if(event.target.tagName.toLowerCase()=='span' && $.inArray(event.target.className, Array('text','active','trigger'))!= -1)
            {
                var parent = event.target.parentNode;
                var offs = $(parent).offset({scroll:false});
                var screenScroll = {x : (offs.left - 3),y : event.pageY - offs.top};
                var isrc = $("#tree_plus").attr('src');
                var ajaxChildSize = $('>ul.ajax',parent).size();
                var ajaxChild = $('>ul.ajax',parent);
                screenScroll.x += 19;
                screenScroll.y = event.pageY - screenScroll.y + 5;

                if(parent.className.indexOf('folder-close')>=0 && ajaxChildSize==0)
                {
                    if(isrc.indexOf('minus')!=-1)$("#tree_plus").attr('src','../images/plus.gif');
                    $("#tree_plus").css({"left": screenScroll.x, "top": screenScroll.y}).show();
                    dragDropTimer = setTimeout(function(){
                        parent.className = parent.className.replace('close','open');
                        $('>ul',parent).show();
                    }, 700);
                }else if(parent.className.indexOf('folder')>=0 && ajaxChildSize==0){
                    if(isrc.indexOf('minus')!=-1)$("#tree_plus").attr('src','../images/plus.gif');
                    $("#tree_plus").css({"left": screenScroll.x, "top": screenScroll.y}).show();
                }else if(parent.className.indexOf('folder-close')>=0 && ajaxChildSize>0)
                {
                    mouseMoved = false;
                    $("#tree_plus").attr('src','../images/minus.gif');
                    $("#tree_plus").css({"left": screenScroll.x, "top": screenScroll.y}).show();

                    $('>ul',parent).show();
                    /*
                        Thanks for the idea of Erik Dohmen
                    */
                    TREE.setAjaxNodes(ajaxChild,parent.id, function(){
                        parent.className = parent.className.replace('close','open');
                        mouseMoved = true;
                        $("#tree_plus").attr('src','../images/plus.gif');
                        $("#tree_plus").css({"left": screenScroll.x, "top": screenScroll.y}).show();
                    });

                }else{
                    if(TREE.option.docToFolderConvert)
                    {
                        $("#tree_plus").css({"left": screenScroll.x, "top": screenScroll.y}).show();
                    }else{
                        $("#tree_plus").hide();
                    }
                }
            }else{
                $("#tree_plus").hide();
            }
            return false;
        }
        return true;
    };
    TREE.dragEnd = function(){
        if(dragDropTimer) clearTimeout(dragDropTimer);
        TREE.eventDestroy();
    };
    TREE.setEventLine = function(obj){
        obj.mouseover(function(){
            if(this.className.indexOf('over')<0 && mousePressed && mouseMoved)
            {
                this.className = this.className.replace('line','line-over');
            }
        }).mouseout(function(){
            if(this.className.indexOf('over')>=0)
            {
                this.className = this.className.replace('-over','');
            }
        }).mouseup(function(){
            if(mousePressed && dragNode_source && mouseMoved)
            {
                dragNode_destination = $(this).parents('li:first');
                TREE.moveNodeToLine(this);
                TREE.eventDestroy();
            }
        });
    };
    TREE.checkNodeIsLast = function(node)
    {
        if(node.className.indexOf('last')>=0)
        {
            var prev_source = dragNode_source.prev().prev();
            if(prev_source.size()>0)
            {
                prev_source[0].className+='-last';
            }
            node.className = node.className.replace('-last','');
        }
    };
    TREE.checkLineIsLast = function(line)
    {
        if(line.className.indexOf('last')>=0)
        {
            var prev = $(line).prev();
            if(prev.size()>0)
            {
                prev[0].className = prev[0].className.replace('-last','');
            }
            dragNode_source[0].className+='-last';
        }
    };
    TREE.eventDestroy = function()
    {
        // added by Erik Dohmen (2BinBusiness.nl), the unbind mousemove TREE.dragStart action
        // like this other mousemove actions binded through other actions ain't removed (use it myself
        // to determine location for context menu)
        $(document).unbind('mousemove',TREE.dragStart).unbind('mouseup').unbind('mousedown');
        $('#drag_container, #tree_plus').remove();
        if(dragNode_source)
        {
            $(dragNode_source).show().prev('.line').show();
        }
        dragNode_destination = dragNode_source = mousePressed = mouseMoved = false;
        //ajaxCache = Array();
    };
    TREE.convertToFolder = function(node){
        node[0].className = node[0].className.replace('doc','folder-open');
        node.append('<ul><li class="line-last"></li></ul>');
        TREE.setTrigger(node[0]);
        TREE.setEventLine($('.line, .line-last', node));
    };
    TREE.convertToDoc = function(node){
        $('>ul', node).remove();
        $('img', node).remove();
        node[0].className = node[0].className.replace(/folder-(open|close)/gi , 'doc');
    };
    TREE.moveNodeToFolder = function(node)
    {
        if(!TREE.option.docToFolderConvert && node[0].className.indexOf('doc')!=-1)
        {
            return true;
        }else if(TREE.option.docToFolderConvert && node[0].className.indexOf('doc')!=-1){
            TREE.convertToFolder(node);
        }
        TREE.checkNodeIsLast(dragNode_source[0]);
        var lastLine = $('>ul >.line-last', node);
        if(lastLine.size()>0)
        {
            TREE.moveNodeToLine(lastLine[0]);
        }
    };
    TREE.moveNodeToLine = function(node){
        TREE.checkNodeIsLast(dragNode_source[0]);
        TREE.checkLineIsLast(node);
        var parent = $(dragNode_source).parents('li:first');
        var line = $(dragNode_source).prev('.line');
        $(node).before(dragNode_source);
        $(dragNode_source).before(line);
        node.className = node.className.replace('-over','');
        var nodeSize = $('>ul >li', parent).not('.line, .line-last').filter(':visible').size();
        if(TREE.option.docToFolderConvert && nodeSize==0)
        {
            TREE.convertToDoc(parent);
        }else if(nodeSize==0)
        {
            parent[0].className=parent[0].className.replace('open','close');
            $('>ul',parent).hide();
        }

        // added by Erik Dohmen (2BinBusiness.nl) select node
        if($('span:first',dragNode_source).attr('class')=='text')
        {
            $('.active',TREE).attr('class','text');
            $('span:first',dragNode_source).attr('class','active');
        }

        if(typeof(TREE.option.afterMove) == 'function')
        {
            var pos = $(dragNode_source).prevAll(':not(.line)').size();
            TREE.option.afterMove($(node).parents('li:first'), $(dragNode_source), pos);
        }
    };

    TREE.addNode = function(id, text, callback)
    {
        var temp_node = $('<li><ul><li id="'+id+'"><span>'+text+'</span></li></ul></li>');
        TREE.setTreeNodes(temp_node);
        dragNode_destination = TREE.getSelected();
        dragNode_source = $('.doc-last',temp_node);
        TREE.moveNodeToFolder(dragNode_destination);
        temp_node.remove();
        if(typeof(callback) == 'function')
        {
            callback(dragNode_destination, dragNode_source);
        }
    };
    TREE.delNode = function(callback)
    {
        dragNode_source = TREE.getSelected();
        TREE.checkNodeIsLast(dragNode_source[0]);
        dragNode_source.prev().remove();
        dragNode_source.remove();
        if(typeof(callback) == 'function')
        {
            callback(dragNode_destination);
        }
    };

    TREE.init = function(obj)
    {
        TREE.setTreeNodes(obj, false);
    };
    TREE.init(ROOT);
});

};
function do_tree_check(e){
event.cancelBubble=true;
//alert(e.checked);
if(e.checked){
e.checked=false;
e.src="../images/tree/iconUnCheckAll.gif";
}else{
if(e.indeter){
e.checked=true;
e.src="../images/tree/iconCheckAll.gif";
}else{
e.checked=true;
e.src="../images/tree/iconCheckAll.gif";
}
}
}