js实现购物车基本功能

js实现购物车加、减、单选、全选、删除、价格总汇、数量总汇；

代码如下：

body部分：

 <div class='cart'>
	 <!-- 头部 -->
		<div class='cart-head u-clearfix'>
			<div class='col col-check u-l'>
				<input type='checkbox' id='all' class='check'>
				<label for='all'>全选</label>
			</div>
			<div class='col col-img u-l'>&nbsp;</div>
			<div class='col col-name u-l'>商品名称</div>
			<div class='col col-price u-l'>单价</div>
			<div class='col col-num u-l'>数量</div>
			<div class='col col-sum u-l'>总额</div>
			<div class='col col-action u-r'>操作</div>
		</div>
			  
		<div class='cart-list'>
				  <div class='list-item'>
					  <!--商品快-->
					  <div class='item-box u-clearfix'>
						  <div class='col col-check u-l'>
						  	 <input type='checkbox' class='check single'>
						  </div>
						  <div class='col col-img u-l'><img src='img/14big.png'></div>
						  <div class='col col-name u-l'>小米14粉</div>
						  <div class='col col-price u-l'>3999</div>
						  <div class='col col-num u-l'>
							<div class='change-goods-num'>
								<a href='javascript:;;' class='reduce'>-</a>
								<input type='text' value='1'>
								<a href='javascript:;;' class='add'>+</a>
							</div>