购物车 加减商品个数效果

html代码：

<ul class="num">
<li class="reduce cannot_select">-</li>
<li><input class="text Quantity" name="Quantity" id="Quantity" value="1" type="text" readonly></li>
<li class="add cannot_select">+</li>
</ul>

js代码：

$(".reduce").click(function () {
var me = $(this), txt = me.parent().find(":text");
var val = Number(txt.val());
val = val <= 1 ? 1 : val - 1;
txt.val(val);
});
$(".add").click(function () {
var me = $(this), txt = me.parent().find(":text");
var val = Number(txt.val());
txt.val(val + 1);
});