js淘宝购物车功能描述：
1、点击“+”，单个商品数量加1，总数量加1；单个商品价格添加，总价也添加。
2、点击“-”，单个商品数量减1，总数量减1；单个商品价格减少，总价也减少。
当该商品数量为0时，点击依然为0；
3、显示出总价，总数量和其中最贵的那个商品的价格。
瞄一眼效果图：
废话不多说，LU代码
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style>
*{padding:0;margin:0;}
#list,p{list-style:none;width:600px;margin:0 auto;}
#list li {width:600px;height:50px;line-height:50px;margin-top:20px;font-size:20px;}
#list li input{width:60px;height:40px;line-height:40px;}
.highlight{color:red;font-size:30px;font-weight:bold;}
</style>
<script>
window.onload = function () {
var oUl = $('list');
var totalNumber = $('totalNum');
var totalPrice = $('totalPrice');
var mostExpensive = $('mostExpensive');
var aLi = oUl.getElementsByTagName('li');
var maxPrice = [0];
for ( var i = 0; i < aLi.length; i++ ) {
price(aLi[i]);
}
function price(oLi) {
var aBtn = oLi.getElementsByTagName('input');
var oStrong = oLi.getElementsByTagName('strong')[0];
var oEm = oLi.getElementsByTagName('em')[0];
var oSpan = oLi.getElementsByTagName('span')[0];
aBtn[0].onclick = function () {
var num = Number(oStrong.innerHTML);
var price = parseFloat(oEm.innerHTML);
var numbers = Number(totalNumber.innerHTML);
var prices = parseFloat(totalPrice.innerHTML);
num--;
if (num === 0) {
// 如果该商品数量为0，,那么就得把它的价格从价格表中清除
var index = maxPrice.indexOf(price);
if (index > -1) maxPrice.splice(index, 1);
} else if (num < 0) {
num = 0;
return;
}
numbers--;
oStrong.innerHTML = num;
oSpan.innerHTML = num * price + '元';
totalNumber.innerHTML = numbers;
totalPrice.innerHTML = prices - (num + 1) * price;
mostExpensive.innerHTML = maxPrice[0];
}
aBtn[1].onclick = function () {
var num = Number(oStrong.innerHTML);
var price = parseFloat(oEm.innerHTML);
var numbers = Number(totalNumber.innerHTML);
var prices = parseFloat(totalPrice.innerHTML);
num++;
numbers++;
if (maxPrice.indexOf(price) < 0) {
maxPrice.push(price)
maxPrice.sort(function (a,b) {return b - a});
}
oStrong.innerHTML = num;
oSpan.innerHTML = num * price + '元';
totalNumber.innerHTML = numbers;
totalPrice.innerHTML = prices + num * price;
mostExpensive.innerHTML = maxPrice[0];
}
}
function $(id) {return document.getElementById(id);}
}
</script>
</head>
<body>
<ul id="list">
<li>
<input type="button" value="-" />
<strong>0</strong>
<input type="button" value="+" />
单价：<em>12.5元</em>
小计：<span class="highlight">0元</span>
</li>
<li>
<input type="button" value="-" />
<strong>0</strong>
<input type="button" value="+" />
单价：<em>10.5元</em>
小计：<span class="highlight">0元</span>
</li>
<li>
<input type="button" value="-" />
<strong>0</strong>
<input type="button" value="+" />
单价：<em>8.5元</em>
小计：<span class="highlight">0元</span>
</li>
<li>
<input type="button" value="-" />
<strong>0</strong>
<input type="button" value="+" />
单价：<em>8元</em>
小计：<span class="highlight">0元</span>
</li>
<li>
<input type="button" value="-" />
<strong>0</strong>
<input type="button" value="+" />
单价：<em>14.5元</em>
小计：<span class="highlight">0元</span>
</li>
</ul>
<p>
商品合计共：<span class="highlight" id="totalNum">0</span>件，
共花费了：<span class="highlight" id="totalPrice">0</span>元<br />
其中最贵的商品单是：<span class="highlight" id="mostExpensive">0</span>元
</p>
</body>
</html>
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。
