原生JS实现可自定义星级评分系统

完整代码实现

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title></title>
 <style>
 *{
  margin: 0;
  padding: 0;
 }
 #star{
  position: absolute;
  left: 0;
  right: 0;
  top: 30px;
  bottom: 0;
  margin: auto;
  width: 80%;
  font-size: 12px;
 }
 #star-div{
  margin:5px;
  font-size: 0;
 }
 #star-div a{
  display: inline-block;
  width: 21px;
  height: 21px;
  background: url(http://files.cnblogs.com/files/susufufu/star0.gif) no-repeat;

 }
 #star-div .on{
  background: url(http://files.cnblogs.com/files/susufufu/star1.gif) no-repeat;
 }
 #star-info{
  position: absolute;
  top: 55px;
  left: -30px;
  display: none;
  width: 155px;
  height: 50px;
  padding: 2px;
  line-height: 17px;
  border-radius: 8px;
  background-color: gold;
  z-index: 5;
 }
 #star-info:before{
  content: '';
  border-bottom: 10px solid gold;
  border-left: 10px solid rgba(0,0,0,0);
  border-right: 10px solid rgba(0,0,0,0);
  position: absolute;
  left: 35px;
  top: -10px;
 }
 #star-span{line-height: 14px}
 #star-info strong,#star-span strong{
  color: red;
 }
 </style>
 <script>
 window.onload = function(){
  var sufuStar = function (){
  //工具函数
  function gbyId(id){return document.getElementById(id);}

  function addEvent(elem,type,func){ //兼容IE
   if(elem.addEventListener){
   elem.addEventListener(type,func,false)
   }else if(elem.attachEvent){
   elem.attachEvent('on'+type,func)
   }
  }
  function getIndex(event) { //兼容IE
   var e = event || window.event;
   var t = e.target || e.srcElement;
   if (t.tagName.toLowerCase() === 'a') {
   return parseInt(t.innerHTML);
   }
  }
  function showInfo(index,msg){
   var info = gbyId('star-info');
   info.style.display = 'block';
   info.style.left = index*21-51+'px';
   info.innerHTML = "<strong> "+index+'分 '+msg[index-1].match(/(.+)\|/)[1]+'<br />'+'</strong>'+msg[index-1].match(/\|(.+)/)[1];
  }
  function appenStar(elem,nums){
   var frag = document.createDocumentFragment(); //为了提高性能,因使用DocumentFragment一次性append,这样页面只重新渲染一次
   for(var i = 0;i<nums;i++){
   var a =document.createElement('a');
   a.innerHTML = i+1;
   a.href = "javascript:;"; //阻止浏览器的点击链接的默认行为
   frag.appendChild(a);
   }
   elem.appendChild(frag);
  }
  //主体函数
  function star(num,myMsg){
   var n = num||5; //当num有值则取其值,无值则取默认值5;
   var clickStar=curentStar=0; //clickStar保存点击状态
   var msg = myMsg||[
   "很不满意|差得太离谱，与卖家描述的严重不符，非常不满",
   "不满意|部分有破损，与卖家描述的不符，不满意",
   "一般|质量一般，没有卖家描述的那么好",
   "满意|质量不错，与卖家描述的基本一致，还是挺满意的",
   "非常满意|质量非常好，与卖家描述的完全一致，非常满意"
   ];
   var starContainer = gbyId('star-div');
   appenStar(starContainer,n);
   addEvent(starContainer,'mouseover',over); //采用事件代理模式(通过<a>标签的父元素starContainer来代理事件)
   addEvent(starContainer,'mouseout',out);
   addEvent(starContainer,'click',click);
   function over(event){
   if(getIndex(event)){ //若getIndex(event)取不到值,说明当前触发事件的目标不是<a>标签
    var index = getIndex(event);
    change(index);
    showInfo(index,msg);
   }
   }
   function out(event){
   change(); //将评分设为已点击状态clickStar
   gbyId('star-info').style.display = 'none'
   }
   function click(event) {
   if (getIndex(event)) {
    var index = getIndex(event);
    clickStar = index; //保存点击状态
    gbyId('star-info').style.display = 'none';
    gbyId('star-span').innerHTML = "<strong>" + index + '分 ' + msg[index - 1].match(/(.+)\|/)[1] + '</strong>'+'<br />'+ msg[index - 1].match(/\|(.+)/)[1];
   }
   }
   function change(index){
   curentStar = index||clickStar;
   for(var i=0;i<n;i++){
    starContainer.children[i].className = i<curentStar ? 'on' : ''
   }
   }
  }
  return {
   star:star
  }
  }(); //这里的()表示函数立即执行,这样变量sufuStar才能调用匿名函数的返回值star

  //调用执行: sufuStar.star(num,myMsg),参数可为空,参数num,myMsg将设为默认值
  sufuStar.star();
 }
 </script>
</head>
<body>
<div id="star">
 <span>点击星星打分:</span>
 <div id="star-div">
 </div>
 <span id="star-span"></span>
 <p id="star-info">
 </p>
</div>
</body>
</html>