這是一個星星評分插件，用原生js寫的。將for(var k = 0)...這段抽出來時，然後執(zhí)行到that.getStarPoint.call(this,point,active)這部分就不行了，這個this是指向star[ i]，如何將star[i]和star[k]有相同的功能呢？
html: (星星暫時用色塊代替)
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>星星評分插件</title>
<meta name="renderer" content="ie-webkit">
<style>
.star{
margin-top: 10px;
}
.star span, .star em{
display: inline-block;
vertical-align: top;
}
.star span{
cursor: pointer;
width: 16px;
height: 16px;
background: #eee;
}
.star span.active{
background: #333;
}
</style>
</head>
<body>
<!-- 建議放評分的盒子也放在同一個盒子里面并且與星星的標簽不一樣，這樣方面dom查找 -->
<!-- 星星可以是圖片，也可以放在css里面 -->
<p class="star">
<span></span>
<span></span>
<span></span>
<span></span>
<span></span>
<em class="star-point"></em>
</p>
</body>
<script type="text/javascript" src="common.js"></script>
<script type="text/javascript">
new Star('.star');
</script>
</html>
js:
;(function(global,undefined){
'use strict'
var _global;
function Star(options){
this.defaultOptions = {
starBox: '.star', //裝星星的obj
starActive: 'active', //鼠標移上去的樣式
starPoint: '.star-point' //星星評分
};
this.opt = this.extend(this.defaultOptions, options || {} || '');
this.star = this.getElem(this.opt.starBox).getElementsByTagName('span');
this.len = this.star.length;
this.init(options);
}
Star.prototype = {
constructor: this,
init: function(options){
var that = this;
var starBox = that.getElem(that.opt.starBox),
starPoint = that.getElem(that.opt.starPoint),
active = that.opt.starActive,
star = starBox.getElementsByTagName('span'),
point = 0;
for(var i = 0; i<this.len; i++){
star[i].index = i;
star[i].onmouseover = function(){
that.clearAllStar.call(this);
/*for(var k = 0; k<this.len; k++){
star[k].className = '';
}*/
for(var j = 0; j<this.index + 1; j++){
star[j].className = active; //經過的就添加active類
}
}
star[i].onmouseout = function(){
for(var j = 0; j<this.index + 1; j++){
star[j].className = ''; //離開的就去掉active類
}
//公用部分
/*for(var k = 0; k<point; k++){
star[k].className = active;
}*/
that.getStarPoint.call(this,point,active);
}
star[i].onclick = function(){ //點擊后的星星個數(shù)以及分數(shù)
point = this.index + 1;
starPoint.innerHTML = point + '分';
//公用部分
/*for(var k = 0; k<point; k++){
star[k].className = active;
}*/
that.getStarPoint.call(this,point,active);
}
}
},
clearAllStar: function(){ //清理所有hover過的星星
for(var k = 0; k<this.len; k++){
this.className = '';
}
},
getStarPoint: function(point,active){ //獲取評分
for(var k = 0; k<point; k++){
this.className = active;
}
},
getElem: function(obj){ //獲取dom元素
return document.querySelector(obj);
},
extend: function(source,value){ //拓展參數(shù)的函數(shù)
for(var i in value){
if(value.hasOwnProperty(i)){
source[i] = value[i];
}
}
return source;
}
}
}())
4
0
0
覺得把 this 綁在 getStarPoint() 意義不大，因為除了當前元素，還有前面的元素都要置為 active，不如就 循環(huán)然後 star[k].className = active;
我覺得，你應該將that作為getStarPoint的上下文，寫作that.getStarPoint.call(that, point, active);，這裡that才是Star實例。
不太理解你說的 “star[i]和star[k]有相同的作用”， 是什麼意思。如果onmouseover 知道自己是哪一個star，可以用閉包把i傳過去：
for(var i = 0; i }star[i].index = i;
star[i].onmouseover = (function(i) {
return function(){
that.clearAllStar.call(this);
/*for(var k = 0; k<this.len; k++){
star[k].className = '';
}*/
for(var j = 0; j<this.index + 1; j++){
star[j].className = active; //經過的就添加active類
}
}
})(i)
.....
