localstorage.js

LocalStorage = {
	preffix: "",

	set: function (key, value, encode) {
		key          = this.preffix + key;
		this.preffix = "";

		if (encode) {
			key   = LocalStorage.encode(key);
			value = LocalStorage.encode(value);
		}

		localStorage.setItem(key, value);
	},

	get: function (key, defaultValue) {
		key          = this.preffix + key;
		defaultValue = defaultValue || "";
		this.preffix = "";

		var value = localStorage.getItem(key);

		if (value === null) {
			value = localStorage.getItem(this.encode(key));

			if (value === null) {
				return defaultValue;
			} else {
				return this.decode(value);
			}
		} else {
			return value;
		}
	},

	remove: function (key) {
		key          = this.preffix + key;
		this.preffix = "";

		localStorage.removeItem(key);
		localStorage.removeItem(this.encode(key));
	},

	exists: function (key) {
		key          = this.preffix + key;
		this.preffix = "";

		var value = localStorage.getItem(key);

		if (value === null) {
			value = localStorage.getItem(this.encode(key));

			if (value === null) {
				return false;
			} else {
				return true;
			}
		} else {
			return true;
		}
	},

	profile: function (name) {
		this.preffix = name + "_";

		return this;
	},

	encode: function (data) {
		return btoa(unescape(encodeURIComponent(data)));
	},

	decode: function (data) {
		return decodeURIComponent(escape(atob(data)));
	}
}