一个用session实现微型购物篮的例子

采于www.phpbuilder.com,稍作补充。代码如下。嘻嘻：）
basket.php:
<?php
include ("evert.inc");
?>
<PRE>
ID    Name    Price
1     Mouse   25.00 <A HREF="<?echo $PHP_SELF; ?>?act=add&id=1&price=25&basket=Mouse">add</A>  <A HREF="<?echo $PHP_SELF; ?>?act=subtract&id=1&price=25&basket=Mouse">subtract</A>
2     Key    100.00 <A HREF="<?echo $PHP_SELF; ?>?act=add&id=2&price=100&basket=Key">add</A>  <A HREF="<?echo $PHP_SELF; ?>?act=subtract&id=2&price=100&basket=Key">subtract</A>
3     Car   5000.00 <A HREF="<?echo $PHP_SELF; ?>?act=add&id=3&price=5000&basket=Car">add</A>  <A HREF="<?echo $PHP_SELF; ?>?act=subtract&id=3&price=5000&basket=Car">subtract</A>
4     Game    25.00 <A HREF="<?echo $PHP_SELF; ?>?act=add&id=4&price=25&basket=Game">add</A>  <A HREF="<?echo $PHP_SELF; ?>?act=subtract&id=4&price=25&basket=Game">subtract</A>
</PRE>
<a href="<?echo $PHP_SELF;?>?logout=1">Logout</a>

evert.inc:
<?php
session_start();
if($logout){
session_destroy();
unset($ses_basket_name);
unset($ses_basket_amount);
unset($ses_basket_price);
unset($ses_basket_id);
unset($ses_basket_items);
}
if ($basket!=""){
if (session_is_registered("ses_basket_items")){
$basket_position_counter=0;
$double=0;

if ($ses_basket_items>0){
foreach ($ses_basket_name as $basket_item){
if ($basket_item==$basket){
$double=1;
$basket_position=$basket_position_counter;

}
$basket_position_counter++;
}
}
if ($double==1){
$oldamount=$ses_basket_amount[$basket_position];
if($act=="add")
$ses_basket_amount[$basket_position]++;
else{
$ses_basket_amount[$basket_position]--;
if($ses_basket_amount[$basket_position]<0)
$ses_basket_amount[$basket_position]=0;
}
$amount=$ses_basket_amount[$basket_position];
$oldprice=$ses_basket_price[$basket_position];
$newprice=$oldamount>0?($oldprice/$oldamount)*$amount:$price;
$ses_basket_price[$basket_position]=$newprice;
}
else{
$ses_basket_name[]=$basket;
$ses_basket_amount[]=1;
$ses_basket_price[]=$price;
$ses_basket_id[]=$id;
$ses_basket_items++;
}
}else{
$ses_basket_items=1;
$ses_basket_name[0]=$basket;
$ses_basket_amount[0]=1;
$ses_basket_price[0]=$price;
$ses_basket_id[0]=$id;
session_register("ses_basket_items");
session_register("ses_basket_name");
session_register("ses_basket_amount");
session_register("ses_basket_price");
session_register("ses_basket_id");
}
}

if ($ses_basket_items>0){
for ($basket_counter=0;$basket_counter<$ses_basket_items;$basket_counter++){
$price=sprintf("%01.2f",$ses_basket_price[$basket_counter]);
$amount=$ses_basket_amount[$basket_counter];
$name=$ses_basket_name[$basket_counter];
if($amount>0){
echo "$amount $name $price";
echo "<BR>n";
}
}
} else {
$ses_basket_items=0;
unset($ses_basket_name);
unset($ses_basket_amount);
unset($ses_basket_price);
unset($ses_basket_id);
}

?>