JS仿JQuery选择器功能

function ZQuery(arg){
 this.elements = [];  //存东西
 this.domString = '';  //保存字符串标签
 if(typeof arg=='function'){
 //DOMReady
 DOMReady(arg);
 }else if(typeof arg=='string'||arg instanceof String){
 if(arg.indexOf('<')!=-1){
  this.domString = arg;
 }else{
  //获取元素
  this.elements = getEle(arg);
  this.length = this.elements.length;
 }
 }else{
 //原生对象-》ZQuery对象
 this.elements.push(arg);
 this.length = this.elements.length;
 }
}
ZQuery.prototype.css = function(name,value){
 if(arguments.length==2){
  //设置一个样式
  for(var i=0;i<this.elements.length;i++){
  this.elements[i].style[name] = value;
  }
 }else{
  if(typeof name=='string'){
  //获取样式
  return getStyle(this.elements[0],name);
  }else{
  //批量设置样式
  var json = name;
  for(var name in json){
   for(var i=0;i<this.elements.length;i++){
   this.elements[i].style[name] = json[name];
   }
  }
  }
 }
};
ZQuery.prototype.attr = function(name,value){
 if(arguments.length==2){
  //设置一个属性
  for(var i=0;i<this.elements.length;i++){
  this.elements[i].setAttribute(name,value);
  }
 }else{
  if(typeof name=='string'){
  //获取属性
  return this.elements[0].getAttribute(name);
  }else{
  //批量设置属性
  var json = name;
  for(var name in json){
   for(var i=0;i<this.elements.length;i++){
   this.elements[i].setAttribute(name,json[name]);
   }
  }
  }
 }
};
ZQuery.prototype.addClass = function(sClass){
 var re = new RegExp('\\b'+sClass+'\\b','g');
 for(var i=0;i<this.elements.length;i++){
 if(this.elements[i].className){
  if(this.elements[i].className.search(re)==-1){
  this.elements[i].className += ' '+sClass;
  }
 }else{
  this.elements[i].className = sClass;
 }
 this.elements[i].className = this.elements[i].className.replace(/^\s+|\s+$/g,'').replace(/\s+/g,' ');
 }
 return this;
};
ZQuery.prototype.removeClass = function(sClass){
 var re = new RegExp('\\b'+sClass+'\\b','g');
 for(var i=0;i<this.elements.length;i++){
 if(this.elements[i].className){
  this.elements[i].className = this.elements[i].className.replace(re,'');
  this.elements[i].className = this.elements[i].className.replace(/^\s+|\s+$/g,'').replace(/\s+/g,' ');
  if(this.elements[i].className==''){
  this.elements[i].removeAttribute('class');
  }
 }
 }
 return this;
};
ZQuery.prototype.html = function(value){
 if(value||value==''){
 //设置
 for(var i=0;i<this.elements.length;i++){
  this.elements[i].innerHTML = value;
 } 
 }else{
 return this.elements[0].innerHTML;
 }
};
ZQuery.prototype.val = function(value){
 if(value||value==''){
 //设置
 for(var i=0;i<this.elements.length;i++){
  this.elements[i].value = value;
 } 
 }else{
 return this.elements[0].value;
 }
};
ZQuery.prototype.show = function(){
 for(var i=0;i<this.elements.length;i++){
 this.elements[i].style.display = 'block';
 }
 return this;
};
ZQuery.prototype.hide = function(){
 for(var i=0;i<this.elements.length;i++){
 this.elements[i].style.display = 'none';
 }
 return this;
};
;'click mouseover mouseout mousedown mouseup mousemove mouseenter mouseleave change keydown keyup contextmenu'.replace(/\w+/g,function(str){
 ZQuery.prototype[str] = function(fn){
 for(var i=0;i<this.elements.length;i++){
  addEvent(this.elements[i],str,fn);
 }
 };
});
ZQuery.prototype.get = function(n){
 for(var i=0;i<this.elements.length;i++){
 if(i==n){
  return this.elements[i];
 }
 }
};
ZQuery.prototype.eq = function(n){
 for(var i=0;i<this.elements.length;i++){
 if(i==n){
  return $(this.elements[i]);
 }
 }
};
ZQuery.prototype.index = function(){
 var aSiblings = this.elements[0].parentNode.children;
 for(var i=0;i<aSiblings.length;i++){
 if(aSiblings[i]==this.elements[0]){
  return i;
 }
 }
};
ZQuery.prototype.hover = function(fn1,fn2){
 for(var i=0;i<this.elements.length;i++){
 $(this.elements[i]).mouseenter(fn1);
 $(this.elements[i]).mouseleave(fn2);
 }
};
ZQuery.prototype.toggle = function(){
 var args = arguments;
 var _this = this;
 for(var i=0;i<this.elements.length;i++){
 ;(function(count){
  $(_this.elements[i]).click(function(ev){
  args[count%args.length].call(this,ev);
  count++;
  });
 })(0);
 }
};
ZQuery.prototype.animate = function(json,options){
 for(var i=0;i<this.elements.length;i++){
 move(this.elements[i],json,options);
 }
};
ZQuery.prototype.appendTo = function(arg){
 var aParent = $(arg);
 for(var i=0;i<aParent.length;i++){
 aParent.get(i).insertAdjacentHTML('beforeEnd',this.domString);
 }
 return this;
};
ZQuery.prototype.prependTo = function(arg){
 var aParent = $(arg);
 for(var i=0;i<aParent.length;i++){
 aParent.get(i).insertAdjacentHTML('afterBegin',this.domString);
 }
 return this;
};
ZQuery.prototype.insertAfter = function(arg){
 var aParent = $(arg);
 for(var i=0;i<aParent.length;i++){
 aParent.get(i).insertAdjacentHTML('afterEnd',this.domString);
 }
 return this;
};
ZQuery.prototype.insertBefore = function(arg){
 var aParent = $(arg);
 for(var i=0;i<aParent.length;i++){
 aParent.get(i).insertAdjacentHTML('beforeBegin',this.domString);
 }
 return this;
};
ZQuery.prototype.remove = function(){
 var oParent = this.elements[0].parentNode;
 for(var i=0;i<this.elements.length;i++){
 oParent.removeChild(this.elements[i]);
 }
 return this;
};
function $(arg){
 return new ZQuery(arg);
};
$.ajax = function(json){
 ajax(json);
};
$.jsonp = function(json){
 jsonp(json);
};
$.fn = ZQuery.prototype;
$.fn.extend = function(json){
 for(var name in json){
 ZQuery.prototype[name] = json[name];
 }
};
function json2url(json){
 var arr = [];
 for(var name in json){
 arr.push(name+'='+encodeURIComponent(json[name]));
 }
 return arr.join('&');
}
function ajax(json){
 json = json||{};
 if(!json.url)return;
 json.type = json.type||'get';
 json.timeout = json.timeout||15000;
 json.data = json.data||{};
 json.data.t = Math.random();
 if(window.XMLHttpRequest){
 var oAjax = new XMLHttpRequest();
 }else{
 var oAjax = new ActiveXObject('Microsoft.XMLHTTP');
 }
 switch(json.type.toLowerCase()){
 case 'get':
  oAjax.open('GET',json.url+'?'+json2url(json.data),true);
  oAjax.send();
  break;
 case 'post':
  oAjax.open('POST',json.url,true);
  oAjax.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
  oAjax.send(json2url(json.data));
  break;
 default:
  oAjax.open('GET',json.url+'?'+json2url(json.data),true);
  oAjax.send();
  break;
 }
 json.loading&&json.loading();
 json.timer = setTimeout(function(){
 oAjax.onreadystatechange = null;
 json.error&&json.error('网络超时。');
 },json.timeout);

 oAjax.onreadystatechange = function(){
 if(oAjax.readyState==4){
  clearTimeout(json.timer);
  if(oAjax.status>=200&&oAjax.status<300||oAjax.status==304){
  json.success&&json.success(oAjax.responseText);
  }else{
  json.error&&json.error(oAjax.status);
  }
 }
 };
}
function jsonp(json){
 json = json||{};
 if(!json.url)return;
 json.timeout = json.timeout||15000;
 json.cbName = json.cbName||'cb';
 json.data = json.data||{};
 json.data[json.cbName] = 'show'+Math.random();
 json.data[json.cbName] = json.data[json.cbName].replace('.','');
 json.timer = setTimeout(function(){
 window[json.data[json.cbName]] = function(res){
  oHead.removeChild(oS);
  json.error&&json.error('网络超时!');
 }
 },json.timeout);
 window[json.data[json.cbName]] = function(res){
 clearTimeout(json.timer);
 oHead.removeChild(oS);
 json.success&&json.success(res);
 }
 var oHead = document.getElementsByTagName('head')[0];
 var oS = document.createElement('script');
 oS.src = json.url+'?'+json2url(json.data);
 oHead.appendChild(oS);
}
function getStyle(obj,sName){
 return (obj.currentStyle||getComputedStyle(obj,false))[sName];
}
function addEvent(obj,sEv,fn){
 if(obj.addEventListener){
 obj.addEventListener(sEv,function(ev){
  var oEvent = ev||event;
  if(fn.call(obj,oEvent)==false){
  oEvent.cancelBubble = true;
  oEvent.preventDefault&&oEvent.preventDefault();
  }
 },false);
 }else{
 obj.attachEvent('on'+sEv,function(){
  var oEvent = ev||event;
  if(fn.call(obj,oEvent)==false){
  oEvent.cancelBubble = true;
  return false;
  }
 });
 }
}
function DOMReady(fn){
 if(document.addEventListener){
 addEvent(document,'DOMContentLoaded',function(){
  fn&&fn();
 });
 }else{
 addEvent(document,'onreadystatechange',function(){
  if(document.readyState=='complete'){
  fn&&fn();
  }
 });
 }
}
function getByClass(oParent,sClass){
 if(oParent.getElementsByClassName){
 return oParent.getElementsByClassName(sClass);
 }else{
 var aResult = [];
 var aEle = oParent.getElementsByTagName('*');
 var re = new RegExp('\\b'+sClass+'\\b','g');
 for(var i=0;i<aEle.length;i++){
  if(aEle[i].className.search(re)!=-1){
  aResult.push(aEle[i]);
  }
 }
 return aResult;
 }
}
function getByStr(aParent,str){
 var aChild = [];
 //遍历父级
 for(var i=0;i<aParent.length;i++){
 switch(str.charAt(0)){
  case '#':
  //#id
  aChild.push(document.getElementById(str.substring(1)));
  break;
  case '.':
  //.class
  var aEle = getByClass(aParent[i],str.substring(1));
  for(var j=0;j<aEle.length;j++){
   aChild.push(aEle[j]);
  }
  break;
  default:
  if(/^\w+\.\w+$/.test(str)){
   //筛选
   //li.on
   var arr = str.split('.');
   var re = new RegExp('\\b'+arr[1]+'\\b','g');
   var aEle = aParent[i].getElementsByTagName(arr[0]);
   for(var j=0;j<aEle.length;j++){
   if(aEle[j].className.search(re)!=-1){
    aChild.push(aEle[j]);
   }
   }
  }else if(/^\w+\[\w+\=\w+\]$/.test(str)){
   //属性
   var arr = str.split(/\[|\=|\]/);
   var aEle = aParent[i].getElementsByTagName(arr[0]);
   for(var j=0;j<aEle.length;j++){
   if(aEle[j].getAttribute(arr[1]) == arr[2]){
    aChild.push(aEle[j]);
   }
   }
  }else if(/^\w+\:\w+(\(\d+\))?$/.test(str)){
   var arr = str.split(/\:|\(|\)/);
   var aEle = aParent[i].getElementsByTagName(arr[0]);
   switch(arr[1]){
   case 'first':
    aChild.push(aEle[0]);
    break;
   case 'last':
    aChild.push(aEle[aEle.length-1]);
    break;
   case 'even':
    for(var j=0;j<aEle.length;j+=2){
    aChild.push(aEle[j]);
    }
    break;
   case 'odd':
    for(var j=1;j<aEle.length;j+=2){
    aChild.push(aEle[j]);
    }
    break;
   case 'eq':
    aChild.push(aEle[arr[2]]);
    break;
   case 'lt':
    for(var j=0;j<arr[2];j++){
    aChild.push(aEle[j]);
    }
    break;
   case 'gt':
    for(var j=parseInt(arr[2])+1;j<aEle.length;j++){
    aChild.push(aEle[j]);
    }
    break;
   }
  }else{
   //标签
   var aEle = aParent[i].getElementsByTagName(str);
   for(var j=0;j<aEle.length;j++){
   aChild.push(aEle[j]);
   }
  }
  break;
 }
 }
 return aChild;
}
function getEle(str){
 var arr = str.replace(/^\s+|\s+$/g,'').split(/\s+/);
 var aParent = [document];
 var aChild = [];
 for(var i=0;i<arr.length;i++){
 aChild = getByStr(aParent,arr[i]);
 //这一次获取到的子级，是下一次获取的父级
 aParent = aChild;
 }
 return aChild;
}
function move(obj,json,options){
 clearInterval(obj.timer); 
 options=options || {};
 options.easing=options.easing|| 'ease-out';
 options.duration=options.duration || 800;
 var count=Math.floor(options.duration/30);
 var start={};
 var dis={};
 for(var name in json){
 start[name]=parseFloat(getStyle(obj,name));
 dis[name]=json[name]-start[name];
 }
 var n=0;
 obj.timer=setInterval(function(){
 n++;
 for(var name in json){
  switch(options.easing){
  case 'linear':
   var a=n/count;
   var cur=start[name]+dis[name]*a;
   break;
  case 'ease-in':
   var a=n/count;
   var cur=start[name]+dis[name]*a*a*a;
   break;
  case 'ease-out':
   var a=1-n/count;
   var cur=start[name]+dis[name]*(1-a*a*a);
   break;
  }
  if(name=='opacity'){
  obj.style.opacity=cur;
  obj.style.filter='alpha(opacity:'+cur*100+')'; 
  }else{
  obj.style[name]=cur+'px';
  }
 }
 if(n==count){
  clearInterval(obj.timer);
  options.complete && options.complete(); 
 }
 },30);
}