今天试用了一下CodeIgniter的Cart类时遇到了个小问题，发现当name的值为中文时，就写入不了session。
在这里特别提醒一下。 在CI手册里也有说明，如下：
$data = array(
'id' => 'sku_123ABC',
'qty' => 1,
'price' => 39.95,
'name' => 'T-Shirt',
'options' => array('Size' => 'L', 'Color' => 'Red')
);
$this->cart->insert($data);
重要说明: 上面的前四个数组索引 (id, qty, price 和name) 是 必需的。如果缺少其中的任何一个，数据将不会被保存到购物车中。第5个索引 (options) 是可选的。当你的商品包含一些相关的选项信息时，你就可以使用它。正如上面所显示的那样，请使用一个数组来保存选项信息。注意：$data['price'] 的值必须大于0
所以，如果以上四个值有一个值为空或者不符合Cart类的过滤规则而被过滤掉那就，数据将不会被保存进购物车中的。
现在我们需要考虑的是，要么把name值也设置为英文或者数字，但这在实际应用中有点不实际。难不成就为了适应CodeIgniter而把所有产品都多搞一个英文名? 当然不了。
我觉得需要用最简单而又不修改CI核心代码的方法来解决这个问题。这样也有利于升级和维护。所以我在application / library/下新建MY_Cart.php文件。 目的是为了重载Cart类的_insert()函数。重载时，直接把Cart类的_insert()方法copy过来。然后把过滤中文的那段代码屏蔽掉就OK了。
MY_Cart.php的代码如下：
Class MY_Cart extends CI_Cart
{
function __construct()
{
parent::__construct();
}
/**
* Insert
*
* @access private
* @param array
* @return bool
*/
function _insert($items = array())
{
// Was any cart data passed? No? Bah...
if ( ! is_array($items) OR count($items) == 0)
{
log_message('error', 'The insert method must be passed an array containing data.');
return FALSE;
}
// --------------------------------------------------------------------
// Does the $items array contain an id, quantity, price, and name? These are required
if ( ! isset($items['id']) OR ! isset($items['qty']) OR ! isset($items['price']) OR ! isset($items['name']))
{
log_message('error', 'The cart array must contain a product ID, quantity, price, and name.');
return FALSE;
}
// --------------------------------------------------------------------
// Prep the quantity. It can only be a number. Duh...
$items['qty'] = trim(preg_replace('/([^0-9])/i', '', $items['qty']));
// Trim any leading zeros
$items['qty'] = trim(preg_replace('/(^[0]+)/i', '', $items['qty']));
// If the quantity is zero or blank there's nothing for us to do
if ( ! is_numeric($items['qty']) OR $items['qty'] == 0)
{
return FALSE;
}
// --------------------------------------------------------------------
// Validate the product ID. It can only be alpha-numeric, dashes, underscores or periods
// Not totally sure we should impose this rule, but it seems prudent to standardize IDs.
// Note: These can be user-specified by setting the $this->product_id_rules variable.
if ( ! preg_match("/^[".$this->product_id_rules."]+$/i", $items['id']))
{
log_message('error', 'Invalid product ID. The product ID can only contain alpha-numeric characters, dashes, and underscores');
return FALSE;
}
// --------------------------------------------------------------------
// Validate the product name. It can only be alpha-numeric, dashes, underscores, colons or periods.
// Note: These can be user-specified by setting the $this->product_name_rules variable.
//以下这段是为了让CART的name支持中文，所以继承Cart类并过滤
/* if ( ! preg_match("/^[".$this->product_name_rules."]+$/i", $items['name']))
{
log_message('error', 'An invalid name was submitted as the product name: '.$items['name'].' The name can only contain alpha-numeric characters, dashes, underscores, colons, and spaces');
return FALSE;
}*/
// --------------------------------------------------------------------
// Prep the price. Remove anything that isn't a number or decimal point.
$items['price'] = trim(preg_replace('/([^0-9\\.])/i', '', $items['price']));
// Trim any leading zeros
$items['price'] = trim(preg_replace('/(^[0]+)/i', '', $items['price']));
// Is the price a valid number?
if ( ! is_numeric($items['price']))
{
log_message('error', 'An invalid price was submitted for product ID: '.$items['id']);
return FALSE;
}
// --------------------------------------------------------------------
// We now need to create a unique identifier for the item being inserted into the cart.
// Every time something is added to the cart it is stored in the master cart array.
// Each row in the cart array, however, must have a unique index that identifies not only
// a particular product, but makes it possible to store identical products with different options.
// For example, what if someone buys two identical t-shirts (same product ID), but in
// different sizes? The product ID (and other attributes, like the name) will be identical for
// both sizes because it's the same shirt. The only difference will be the size.
// Internally, we need to treat identical submissions, but with different options, as a unique product.
// Our solution is to convert the options array to a string and MD5 it along with the product ID.
// This becomes the unique "row ID"
if (isset($items['options']) AND count($items['options']) > 0)
{
$rowid = md5($items['id'].implode('', $items['options']));
}
else
{
// No options were submitted so we simply MD5 the product ID.
// Technically, we don't need to MD5 the ID in this case, but it makes
// sense to standardize the format of array indexes for both conditions
$rowid = md5($items['id']);
}
// --------------------------------------------------------------------
// Now that we have our unique "row ID", we'll add our cart items to the master array
// let's unset this first, just to make sure our index contains only the data from this submission
unset($this->_cart_contents[$rowid]);
// Create a new index with our new row ID
$this->_cart_contents[$rowid]['rowid'] = $rowid;
// And add the new items to the cart array
foreach ($items as $key => $val)
{
$this->_cart_contents[$rowid][$key] = $val;
}
// Woot!
return TRUE;
}
// --------------------------------------------------------------------
}
?>