用php数组和cookie实现购物车功能,实现的方法是：把cookie存入array，对array进行增加、删除、修改操作，array中的每一组记录都是一个商品的信息(个数，价格等)<br />
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解决购物车的思路是用cookie记录一个二维数组。一维代表每一个商品，二维包含了商品的id,商品的数量...等可以自行增加，反正都是二维了，自己愿意带多少个商品属性就加上去。<br />
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对购物车里商品的操作一般有以下几个：<br />
添加商品，修改商品数量，删除商品，清空购物车。<br />
这几个操作都是针对cookie的。每次把cookie中的数组取出来，增加、修改、删除一番，再记录到cookie中。至于清空购物车，那就更简单了，直接设置同名的cookie为空就可以了。 <br />
具体代码如下:<br />
//加入购物车 <br />
function addcart($goods_id,$goods_num){ <br />
$cur_cart_array = unserialize(stripslashes($_COOKIE['shop_cart_info'])); <br />
if($cur_cart_array==""){ <br />
$cart_info[0][] = $goods_id; <br />
$cart_info[0][] = $goods_num; <br />
setcookie("shop_cart_info",serialize($cart_info)); <br />
}elseif($cur_cart_array<>""){ <br />
//返回数组键名倒序取最大 <br />
$ar_keys = array_keys($cur_cart_array); <br />
rsort($ar_keys); <br />
$max_array_keyid = $ar_keys[0]+1; <br />
//遍历当前的购物车数组 <br />
//遍历每个商品信息数组的0值，如果键值为0且货号相同则购物车存在相同货品 <br />
foreach($cur_cart_array as $goods_current_cart){ <br />
foreach($goods_current_cart as $key=>$goods_current_id){ <br />
if($key == 0 and $goods_current_id == $goods_id){ <br />
echo "<script language=javascript>"; <br />
echo "if(confirm('购物车已经有该商品，继续购物按----确定!查看购物车按----取消!'))"; <br />
echo "{history.go(-1)}"; <br />
echo "else{window.location.href='xqs_cart.php'}"; <br />
echo "</script>"; <br />
exit(); <br />
} <br />
} <br />
} <br />
$cur_cart_array[$max_array_keyid][] = $goods_id; <br />
$cur_cart_array[$max_array_keyid][] = $goods_num; <br />
setcookie("shop_cart_info",serialize($cur_cart_array)); <br />
} <br />
} <br />
//从购物车删除 <br />
function delcart($goods_array_id){<br />
$cur_goods_array = unserialize(stripslashes($_COOKIE['shop_cart_info'])); <br />
//删除该商品在数组中的位置 <br />
unset($cur_goods_array[$goods_array_id]); <br />
setcookie("shop_cart_info",serialize($cur_goods_array)); <br />
}<br />
//修改购物车货品数量 <br />
function update_cart($up_id,$up_num,$goods_ids){ <br />
//先清空cookie,以便重新设置，传递过来三个数组参数 1数组的标识 2商品数量数组 3商品编号数组 <br />
//如果不清空cookie则无法处理数量为零的商品 <br />
setcookie("shop_cart_info",""); <br />
foreach($up_id as $song){ <br />
//先返回数组当前单元；再把指针向下移动一个位置 <br />
$goods_nums = current($up_num); <br />
$goods_id = current($goods_ids); <br />
next($up_num); <br />
next($goods_ids); <br />
//当商品数量为空的时候，注销此处的数组值并用continue 2 语句避开下面的操作，继续做foreach循环 <br />
while($goods_nums == 0){ <br />
unset($song); <br />
continue 2; <br />
} <br />
$cur_goods_array[$song][0] = $goods_id; <br />
$cur_goods_array[$song][1] = $goods_nums; <br />
} <br />
setcookie("shop_cart_info",serialize($cur_goods_array)); <br />
}