js实现无限级树形导航列表效果代码_javascript技巧

 

DOMhelp={
 debugWindowId:'DOMhelpdebug',
 init:function(){
 if(!document.getElementById || !document.createTextNode){return;}
 },
 lastSibling:function(node){
 var tempObj=node.parentNode.lastChild;
 while(tempObj.nodeType!=1 && tempObj.previousSibling!=null){
 tempObj=tempObj.previousSibling;
 }
 return (tempObj.nodeType==1)?tempObj:false;
 },
 firstSibling:function(node){
 var tempObj=node.parentNode.firstChild;
 while(tempObj.nodeType!=1 && tempObj.nextSibling!=null){
 tempObj=tempObj.nextSibling;
 }
 return (tempObj.nodeType==1)?tempObj:false;
 },
 getText:function(node){
 if(!node.hasChildNodes()){return false;}
 var reg=/^\s+$/;
 var tempObj=node.firstChild;
 while(tempObj.nodeType!=3 && tempObj.nextSibling!=null || reg.test(tempObj.nodeValue)){
 tempObj=tempObj.nextSibling;
 }
 return tempObj.nodeType==3?tempObj.nodeValue:false;
 },
 setText:function(node,txt){
 if(!node.hasChildNodes()){return false;}
 var reg=/^\s+$/;
 var tempObj=node.firstChild;
 while(tempObj.nodeType!=3 && tempObj.nextSibling!=null || reg.test(tempObj.nodeValue)){
 tempObj=tempObj.nextSibling;
 }
 if(tempObj.nodeType==3){tempObj.nodeValue=txt}else{return false;}
 },
 createLink:function(to,txt){
 var tempObj=document.createElement('a');
 tempObj.appendChild(document.createTextNode(txt));
 tempObj.setAttribute('href',to);
 return tempObj;
 },
 createTextElm:function(elm,txt){
 var tempObj=document.createElement(elm);
 tempObj.appendChild(document.createTextNode(txt));
 return tempObj;
 },
 closestSibling:function(node,direction){
 var tempObj;
 if(direction==-1 && node.previousSibling!=null){
 tempObj=node.previousSibling;
 while(tempObj.nodeType!=1 && tempObj.previousSibling!=null){
 tempObj=tempObj.previousSibling;
 }
 }else if(direction==1 && node.nextSibling!=null){
 tempObj=node.nextSibling;
 while(tempObj.nodeType!=1 && tempObj.nextSibling!=null){
 tempObj=tempObj.nextSibling;
 }
 }
 return tempObj.nodeType==1?tempObj:false;
 },
 initDebug:function(){
 if(DOMhelp.debug){DOMhelp.stopDebug();}
 DOMhelp.debug=document.createElement('div');
 DOMhelp.debug.setAttribute('id',DOMhelp.debugWindowId);
 document.body.insertBefore(DOMhelp.debug,document.body.firstChild);
 },
 setDebug:function(bug){
 if(!DOMhelp.debug){DOMhelp.initDebug();}
 DOMhelp.debug.innerHTML+=bug+'\n';
 },
 stopDebug:function(){
 if(DOMhelp.debug){
 DOMhelp.debug.parentNode.removeChild(DOMhelp.debug);
 DOMhelp.debug=null;
 }
 },
 getKey:function(e){
 if(window.event){
 var key = window.event.keyCode;
 } else if(e){
 var key=e.keyCode;
 }
 return key;
 },
/* helper methods */
 getTarget:function(e){
 var target = window.event ? window.event.srcElement : e ? e.target : null;
 if (!target){return false;}
 while(target.nodeType!=1 && target.nodeName.toLowerCase()!='body'){
 target=target.parentNode;
 }
 return target;
 },
 stopBubble:function(e){
 if(window.event && window.event.cancelBubble){
 window.event.cancelBubble = true;
 } 
 if (e && e.stopPropagation){
 e.stopPropagation();
 }
 },
 stopDefault:function(e){
 if(window.event && window.event.returnValue){
 window.event.returnValue = false;
 } 
 if (e && e.preventDefault){
 e.preventDefault();
 }
 },
 cancelClick:function(e){
 if (window.event){
 window.event.cancelBubble = true;
 window.event.returnValue = false;
 }
 if (e && e.stopPropagation && e.preventDefault){
 e.stopPropagation();
 e.preventDefault();
 }
 },
 addEvent: function(elm, evType, fn, useCapture){
 if (elm.addEventListener){
 elm.addEventListener(evType, fn, useCapture);
 return true;
 } else if (elm.attachEvent) {
 var r = elm.attachEvent('on' + evType, fn);
 return r;
 } else {
 elm['on' + evType] = fn;
 }
 },
 cssjs:function(a,o,c1,c2){
 switch (a){
 case 'swap':
 o.className=!DOMhelp.cssjs('check',o,c1)?o.className.replace(c2,c1):o.className.replace(c1,c2);
 break;
 case 'add':
 if(!DOMhelp.cssjs('check',o,c1)){o.className+=o.className?' '+c1:c1;}
 break;
 case 'remove':
 var rep=o.className.match(' '+c1)?' '+c1:c1;
 o.className=o.className.replace(rep,'');
 break;
 case 'check':
 var found=false;
 var temparray=o.className.split(' ');
 for(var i=0;i