<?php
/**
 *
 * @author quanshuidingdang
 */
class Cart {
 //物品id及名称规则,调试信息控制
 private $product_id_rule = \'\\.a-z0-9-_\'; //小写字母 | 数字 | ._-
 private $product_name_rule = \'\\.\\:a-z0-9-_\';//小写字母 | 数字 | ._-:
 private $debug = TRUE;
 //购物车
 private $_cart_contents = array();
 /**
  * 构造函数
  *
  * @param array
  */
 public function __construct() {
  //是否第一次使用?
  if(isset($_SESSION[\'cart_contents\'])) {
   $this->_cart_contents = $_SESSION[\'cart_contents\'];
  } else {
   $this->_cart_contents[\'cart_total\'] = 0;
   $this->_cart_contents[\'total_items\'] = 0;
  }
  if($this->debug === TRUE) {
   //$this->_log(\"cart_create_success\");
  }
 }
 /**
  * 将物品加入购物车
  *
  * @access public
  * @param array 一维或多维数组,必须包含键值名: 
      id -> 物品ID标识, 
      qty -> 数量(quantity), 
      price -> 单价(price), 
      name -> 物品姓名
  * @return bool
  */
 public function insert($items = array()) {
  //输入物品参数异常
  if( ! is_array($items) OR count($items) == 0) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_no_items_insert\");
   }
   return FALSE;
  }
  //物品参数处理
  $save_cart = FALSE;
  if(isset($items[\'id\'])) {
   if($this->_insert($items) === TRUE) {
    $save_cart = TRUE;
   }
  } else {
   foreach($items as $val) {
    if(is_array($val) AND isset($val[\'id\'])) {
     if($this->_insert($val) == TRUE) {
      $save_cart = TRUE;
     }
    }
   }
  }
  //当插入成功后保存数据到session
  if($save_cart) {
   $this->_save_cart();
   return TRUE;
  }
  return FALSE;
 }
 /**
  * 更新购物车物品信息
  *
  * @access public
  * @param array
  * @return bool
  */
 public function update($items = array()) {
  //输入物品参数异常
  if( !is_array($items) OR count($items) == 0) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_no_items_insert\");
   }
   return FALSE;
  }
  //物品参数处理
  $save_cart = FALSE;
  if(isset($items[\'rowid\']) AND isset($items[\'qty\'])) {
   if($this->_update($items) === TRUE) {
    $save_cart = TRUE;
   }
  } else {
   foreach($items as $val) {
    if(is_array($val) AND isset($val[\'rowid\']) AND isset($val[\'qty\'])) {
     if($this->_update($val) === TRUE) {
      $save_cart = TRUE;
     }
    }
   }
  }
  //当更新成功后保存数据到session
  if($save_cart) {
   $this->_save_cart();
   return TRUE;
  }
  return FALSE;
 }
 /**
  * 获取购物车物品总金额
  *
  * @return int
  */
 public function total() {
  return $this->_cart_contents[\'cart_total\'];
 }
 /**
  * 获取购物车物品种类
  *
  * @return int
  */
 public function total_items() {
  return $this->_cart_contents[\'total_items\'];
 }
 /**
  * 获取购物车
  *
  * @return array
  */
 public function contents() {
  return $this->_cart_contents;
 }
 /**
  * 获取购物车物品options
  *
  * @param string
  * @return array
  */
 public function options($rowid = \'\') {
  if($this->has_options($rowid)) {
   return $this->_cart_contents[$rowid][\'options\'];
  } else {
   return array();
  }
 }
 /**
  * 清空购物车
  *
  */
 public function destroy() {
  unset($this->_cart_contents);
  $this->_cart_contents[\'cart_total\'] = 0;
  $this->_cart_contents[\'total_items\'] = 0;
  unset($_SESSION[\'cart_contents\']);
 }
 /**
  * 判断购物车物品是否有options选项
  * 
  * @param string
  * @return bool
  */
 private function has_options($rowid = \'\') {
  if( ! isset($this->_cart_contents[$rowid][\'options\']) OR count($this->_cart_contents[$rowid][\'options\']) === 0) {
   return FALSE;
  }
  return TRUE;
 }
 /**
  * 插入数据
  *
  * @access private 
  * @param array
  * @return bool
  */
 private function _insert($items = array()) {
  //输入物品参数异常
  if( ! is_array($items) OR count($items) == 0) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_no_data_insert\");
   }
   return FALSE;
  }
  //如果物品参数无效（无id/qty/price/name）
  if( ! isset($items[\'id\']) OR ! isset($items[\'qty\']) OR ! isset($items[\'price\']) OR ! isset($items[\'name\'])) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data_invalid\");
   }
   return FALSE;
  }
  //去除物品数量左零及非数字字符
  $items[\'qty\'] = trim(preg_replace(\'/([^0-9])/i\', \'\', $items[\'qty\']));
  $items[\'qty\'] = trim(preg_replace(\'/^([0]+)/i\', \'\', $items[\'qty\']));
  //如果物品数量为0，或非数字，则我们对购物车不做任何处理!
  if( ! is_numeric($items[\'qty\']) OR $items[\'qty\'] == 0) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data(qty)_invalid\");
   }
   return FALSE;
  }
  //物品ID正则判断
  if( ! preg_match(\'/^[\'.$this->product_id_rule.\']+$/i\', $items[\'id\'])) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data(id)_invalid\");
   }
   return FALSE;
  }
  //物品名称正则判断
  if( ! preg_match(\'/^[\'.$this->product_name_rule.\']+$/i\', $items[\'name\'])) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data(name)_invalid\");
   }
   return FALSE;
  }
  //去除物品单价左零及非数字（带小数点）字符
  $items[\'price\'] = trim(preg_replace(\'/([^0-9\\.])/i\', \'\', $items[\'price\']));
  $items[\'price\'] = trim(preg_replace(\'/^([0]+)/i\', \'\', $items[\'price\']));
  //如果物品单价非数字
  if( ! is_numeric($items[\'price\'])) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data(price)_invalid\");
   }
   return FALSE;
  }
  //生成物品的唯一id
  if(isset($items[\'options\']) AND count($items[\'options\']) >0) {
   $rowid = md5($items[\'id\'].implode(\'\', $items[\'options\']));
  } else {
   $rowid = md5($items[\'id\']);
  }
  //加入物品到购物车
  unset($this->_cart_contents[$rowid]);
  $this->_cart_contents[$rowid][\'rowid\'] = $rowid;
  foreach($items as $key => $val) {
   $this->_cart_contents[$rowid][$key] = $val;
  }
  return TRUE;
 }
 /**
  * 更新购物车物品信息（私有）
  *
  * @access private
  * @param array
  * @return bool
  */
 private function _update($items = array()) {
  //输入物品参数异常
  if( ! isset($items[\'rowid\']) OR ! isset($items[\'qty\']) OR ! isset($this->_cart_contents[$items[\'rowid\']])) {
   if($this->debug == TRUE) {
    $this->_log(\"cart_items_data_invalid\");
   }
   return FALSE;
  }
  //去除物品数量左零及非数字字符
  $items[\'qty\'] = preg_replace(\'/([^0-9])/i\', \'\', $items[\'qty\']);
  $items[\'qty\'] = preg_replace(\'/^([0]+)/i\', \'\', $items[\'qty\']);
  //如果物品数量非数字，对购物车不做任何处理!
  if( ! is_numeric($items[\'qty\'])) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data(qty)_invalid\");
   }
   return FALSE;
  }
  //如果购物车物品数量与需要更新的物品数量一致，则不需要更新
  if($this->_cart_contents[$items[\'rowid\']][\'qty\'] == $items[\'qty\']) {
   if($this->debug === TRUE) {
    $this->_log(\"cart_items_data(qty)_equal\");
   }
   return FALSE;
  }
  //如果需要更新的物品数量等于0，表示不需要这件物品，从购物车种清除
  //否则修改购物车物品数量等于输入的物品数量
  if($items[\'qty\'] == 0) {
   unset($this->_cart_contents[$items[\'rowid\']]);
  } else {
   $this->_cart_contents[$items[\'rowid\']][\'qty\'] = $items[\'qty\'];
  }
  return TRUE;
 }
 /**
  * 保存购物车数据到session
  * 
  * @access private
  * @return bool
  */
 private function _save_cart() {
  //首先清除购物车总物品种类及总金额
  unset($this->_cart_contents[\'total_items\']);
  unset($this->_cart_contents[\'cart_total\']);
  //然后遍历数组统计物品种类及总金额
  $total = 0;
  foreach($this->_cart_contents as $key => $val) {
   if( ! is_array($val) OR ! isset($val[\'price\']) OR ! isset($val[\'qty\'])) {
    continue;
   }
   $total += ($val[\'price\'] * $val[\'qty\']);
   //每种物品的总金额
   $this->_cart_contents[$key][\'subtotal\'] = ($val[\'price\'] * $val[\'qty\']);
  }
  //设置购物车总物品种类及总金额
  $this->_cart_contents[\'total_items\'] = count($this->_cart_contents);
  $this->_cart_contents[\'cart_total\'] = $total;
  //如果购物车的元素个数少于等于2，说明购物车为空
  if(count($this->_cart_contents) <= 2) {
   unset($_SESSION[\'cart_contents\']);
   return FALSE;
  }
  //保存购物车数据到session
  $_SESSION[\'cart_contents\'] = $this->_cart_contents;
  return TRUE;
 }
 /**
  * 日志记录
  *
  * @access private
  * @param string
  * @return bool
  */
 private function _log($msg) {
  return @file_put_contents(\'cart_err.log\', $msg, FILE_APPEND);
 }
}
/*End of file cart.php*/
/*Location /htdocs/cart.php*/

<?php
session_start();
require_once(\'cart.php\');
$items = array(
   0 => array(
   \'id\' => \'sp001\',
   \'qty\' => 20,
   \'price\' => \'10.50\',
   \'name\' => \'a002\',
   \'options\' => array(
       \'made\' => \'china\',
       \'company\' => \'bgi\'
       )
   ),
   1 => array(
   \'id\' => \'sp002\',
   \'qty\' => 1,
   \'price\' => \'3.50\',
   \'name\' => \'b002\'
   )
  );
$arr = array(
   \'rowid\' => \'86dbb7cb58a667558b4bbb1f60330028\',
   \'qty\' => 21
  );
$cart = new Cart();
$cart->insert($items);
//var_dump($cart->contents());
$cart->update($arr);
var_dump($cart->contents());
//$cart->destroy();
//var_dump($_SESSION[\'cart_contents\']);
/*end of php*/