js cookie存储方法

/*!
 * jQuery Cookie Plugin v1.4.0
 * https://github.com/carhartl/jquery-cookie
 *
 * Copyright 2013 Klaus Hartl
 * Released under the MIT license
 * Usage
 
Create session cookie:

$.cookie('the_cookie', 'the_value');
Create expiring cookie, 7 days from then:

$.cookie('the_cookie', 'the_value', { expires: 7 });
Create expiring cookie, valid across entire site:

$.cookie('the_cookie', 'the_value', { expires: 7, path: '/' });
Read cookie:

$.cookie('the_cookie'); // => "the_value"
$.cookie('not_existing'); // => undefined
Read all available cookies:

$.cookie(); // => { "the_cookie": "the_value", "...remaining": "cookies" }
Delete cookie:

// Returns true when cookie was found, false when no cookie was found...
$.removeCookie('the_cookie');

// Same path as when the cookie was written...
$.removeCookie('the_cookie', { path: '/' });
 */
(function(factory) {
    if (typeof define === 'function' && define.amd) {
        // AMD. Register as anonymous module.
        define(['jquery'], factory);
    } else {
        // Browser globals.
        factory(jQuery);
    }
}(function($) {

var pluses = /\+/g;

function encode(s) {
        return config.raw ? s : encodeURIComponent(s);
    }

function decode(s) {
        return config.raw ? s : decodeURIComponent(s);
    }

function stringifyCookieValue(value) {
        return encode(config.json ? JSON.stringify(value) : String(value));
    }

function parseCookieValue(s) {
        if (s.indexOf('"') === 0) {
            // This is a quoted cookie as according to RFC2068, unescape...
            s = s.slice(1, -1).replace(/\\"/g, '"').replace(/\\\\/g, '\\');
        }

try {
            // Replace server-side written pluses with spaces.
            // If we can't decode the cookie, ignore it, it's unusable.
            s = decodeURIComponent(s.replace(pluses, ' '));
        } catch (e) {
            return;
        }

try {
            // If we can't parse the cookie, ignore it, it's unusable.
            return config.json ? JSON.parse(s) : s;
        } catch (e) {}
    }

function read(s, converter) {
        var value = config.raw ? s : parseCookieValue(s);
        return $.isFunction(converter) ? converter(value) : value;
    }

var config = $.cookie = function(key, value, options) {

// Write
        if (value !== undefined && !$.isFunction(value)) {
            options = $.extend({}, config.defaults, options);

if (typeof options.expires === 'number') {
                var days = options.expires,
                    t = options.expires = new Date();
                t.setDate(t.getDate() + days);
            }

return (document.cookie = [
                encode(key), '=', stringifyCookieValue(value),
                options.expires ? '; expires=' + options.expires.toUTCString() : '', // use expires attribute, max-age is not supported by IE
                options.path ? '; path=' + options.path : '',
                options.domain ? '; domain=' + options.domain : '',
                options.secure ? '; secure' : ''
            ].join(''));
        }

// Read

var result = key ? undefined : {};

// To prevent the for loop in the first place assign an empty array
        // in case there are no cookies at all. Also prevents odd result when
        // calling $.cookie().
        var cookies = document.cookie ? document.cookie.split('; ') : [];

for (var i = 0, l = cookies.length; i < l; i++) {
            var parts = cookies[i].split('=');
            var name = decode(parts.shift());
            var cookie = parts.join('=');

if (key && key === name) {
                // If second argument (value) is a function it's a converter...
                result = read(cookie, value);
                break;
            }

// Prevent storing a cookie that we couldn't decode.
            if (!key && (cookie = read(cookie)) !== undefined) {
                result[name] = cookie;
            }
        }

return result;
    };

config.defaults = {};

$.removeCookie = function(key, options) {
        if ($.cookie(key) !== undefined) {
            // Must not alter options, thus extending a fresh object...
            $.cookie(key, '', $.extend({}, options, {
                expires: -1
            }));
            return true;
        }
        return false;
    };

}));

另外，目前javascript使用非常多的json格式，如果希望存储在本地，可以直接调用JSON.stringify()将其转为字符串。读取出来后调用JSON.parse()将字符串转为json格式，如下所示：

var obj = {
           "12345":{
               "id":"45",
               "name":"pp"
           }
       }
$.cookie("test",JSON.stringify(obj));
console.log(JSON.parse($.cookie("test")))