Polyfill localStore - Object support

store.js

/**
 * Polyfill localStore
 * @type {Object}
 * @var days es opcional y solo para el modo cookies
 * @attributes store.set(key,value[,days]) // Setea un valor
 * @attributes store.setObj(key,obj[,days]) // Setea un valor con un objeto
 * @attributes store.get(key) // Obtiene un valor
 * @attributes store.getObj(key) // Obtine un objeto
 * @attributes store.del(key) // Elimina un valor
 * @attributes store.localStoreSupport() // Soporte localStorage
 */
window.store = {
    localStoreSupport: function() {
        try {
            return "localStorage" in window && window["localStorage"] !== null;
        } catch (e) {
            return false;
        }
    },
    setObj: function(key, obj, days) {
    	var expires = "";
    	if (days) {
    	    var date = new Date();
    	    date.setTime(date.getTime() + days * 24 * 60 * 60 * 1e3);
    	    expires = "; expires=" + date.toGMTString();
    	}
        if (this.localStoreSupport()) {
            return localStorage.setItem(key, JSON.stringify(obj));
        } else {
            document.cookie = key + "=" + JSON.stringify(obj) + expires + "; path=/";
        }
    },
    getObj: function(key) {
        if (this.localStoreSupport()) {
            return JSON.parse(localStorage.getItem(key));
        } else {
            var keyEQ = key + "=";
            var ca = document.cookie.split(";");
            for (var i = 0; i < ca.length; i++) {
                var c = ca[i];
                while (c.charAt(0) == " ") c = c.substring(1, c.length);
                if (c.indexOf(keyEQ) === 0) return JSON.parse(c.substring(keyEQ.length, c.length));
            }
            return null;
        }
    },
    set: function(key, value, days) {
        var expires = "";
        if (days) {
            var date = new Date();
            date.setTime(date.getTime() + days * 24 * 60 * 60 * 1e3);
            expires = "; expires=" + date.toGMTString();
        }
        if (this.localStoreSupport()) {
            localStorage.setItem(key, value);
        } else {
            document.cookie = key + "=" + value + expires + "; path=/";
        }
    },
    get: function(key) {
        if (this.localStoreSupport()) {
            return localStorage.getItem(key);
        } else {
            var keyEQ = key + "=";
            var ca = document.cookie.split(";");
            for (var i = 0; i < ca.length; i++) {
                var c = ca[i];
                while (c.charAt(0) == " ") c = c.substring(1, c.length);
                if (c.indexOf(keyEQ) === 0) return c.substring(keyEQ.length, c.length);
            }
            return null;
        }
    },
    exist: function(key) {
        return (this.get(key) === null) ? false : true;
    },
    del: function(key) {
        if (this.localStoreSupport()) {
            localStorage.removeItem(key);
        } else {
            this.set(key, "", -1);
        }
    }
};