jQuery基于json与cookie实现购物车的方法

[{'ProductID':ABC','Num':'1'},{'ProductID':DEF,'Num':'2'}]

/*
添加商品及数量到购物车cookie中,返回当前商品在cookie中的总数
*/
function AddToShoppingCar(id, num) {
 var _num = 1;
 if (num != undefined)
 _num = num;
 var totalNum = _num; //总数默认为传入参数
 var cookieSet = { expires: 7, path: '/' }; //设置cookie路径的
// $.cookie(cookieProductID, null, cookieSet);//清除Cookie
 var jsonStr = "[{'ProductID':'" + id + "','Num':'" + _num + "'}]"; //构造json字符串,id是商品id num是这个商品的数量
 if ($.cookie(cookieProductID) == null) {
 $.cookie(cookieProductID, jsonStr, cookieSet); //如果没有这个cookie就设置他
 }
 else {
 var jsonObj = eval('(' + $.cookie(cookieProductID) + ')'); //如果有，把json字符串转换成对象
 var findProduct = false;//是否找到产品ID,找到则为TRUE,否则为FALSH
 for (var obj in jsonObj) {
 if (jsonObj[obj].ProductID == id) {
 jsonObj[obj].Num = Number(jsonObj[obj].Num) + _num;
 totalNum = jsonObj[obj].Num;
 findProduct = true;
 break;
 }
 }
 if (findProduct == false) { //没找到,则添加
 jsonObj[jsonObj.length] = new Object();
 jsonObj[jsonObj.length - 1].ProductID = id;
 jsonObj[jsonObj.length - 1].Num = num;
 }
 $.cookie(cookieProductID, JSON.stringify(jsonObj), cookieSet); //写入coockie JSON需要json2.js支持
 }
 return totalNum;
 // alert($.cookie(cookieProductID));
}

//以下为cookie插件代码
jQuery.cookie = function(name, value, options) {
 if (typeof value != 'undefined') { // name and value given, set cookie
 options = options || {};
 if (value === null) {
 value = '';
 options.expires = -1;
 }
 var expires = '';
 if (options.expires && (typeof options.expires == 'number' || options.expires.toUTCString)) {
 var date;
 if (typeof options.expires == 'number') {
 date = new Date();
 date.setTime(date.getTime() + (options.expires * 24 * 60 * 60 * 1000));
 } else {
 date = options.expires;
 }
 expires = '; expires=' + date.toUTCString(); // use expires attribute, max-age is not supported by IE
 }
 var path = options.path ? '; path=' + options.path : '';
 var domain = options.domain ? '; domain=' + options.domain : '';
 var secure = options.secure ? '; secure' : '';
 document.cookie = [name, '=', encodeURIComponent(value), expires, path, domain, secure].join('');
 } else { // only name given, get cookie
 var cookieValue = null;
 if (document.cookie && document.cookie != '') {
 var cookies = document.cookie.split(';');
 for (var i = 0; i < cookies.length; i++) {
 var cookie = jQuery.trim(cookies[i]);
 // Does this cookie string begin with the name we want?
 if (cookie.substring(0, name.length + 1) == (name + '=')) {
 cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
 break;
 }
 }
 }
 return cookieValue;
 }
};