简单cookie时效设置

   首先需要引用两个js，一个是jquery，另一个是jquery.cookie.js

		<script src="js/jquery-3.3.1.min.js" type="text/javascript" charset="utf-8"></script>
		<script src="js/jquery.cookie.js" type="text/javascript" charset="utf-8"></script>

原本js处理cookie的方法

    创建cookie

document.cookie="name=val";

name是cookie存储名字，val是值

    cookie添加过期时间

document.cookie="name=val"; expires=Thu, 18 Dec 2013 12:00:00 GMT";

使用起来不是很方便现在简化了，引用完两个js文件

    $.cookie("name", "val", { expires: 30 }); 

直接这样就可以了，括号里前两个是cookie存储名字和值，后一个为时间，单位天

jquery.cookie.js：

(function (factory) {
	if (typeof define === 'function' && define.amd) {
		define(['jquery'], factory);
	} else if (typeof exports === 'object') {
		factory(require('jquery'));
	} else {
		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) {
			s = s.slice(1, -1).replace(/\\"/g, '"').replace(/\\\\/g, '\\');
		}
		try {
			s = decodeURIComponent(s.replace(pluses, ' '));
			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 = $.cookie = function (key, value, options) {
		if (value !== undefined && !$.isFunction(value)) {
			options = $.extend({}, config.defaults, options);
			if (typeof options.expires === 'number') {
				var days = options.expires, t = options.expires = new Date();
				t.setTime(+t + days * 864e+5);
			}
			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(''));
		}
		var result = key ? undefined : {};
		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) {
				result = read(cookie, value);
				break;
			}
			if (!key && (cookie = read(cookie)) !== undefined) {
				result[name] = cookie;
			}
		}
		return result;
	};
	config.defaults = {};
	$.removeCookie = function (key, options) {
		if ($.cookie(key) === undefined) {
			return false;
		}
		$.cookie(key, '', $.extend({}, options, { expires: -1 }));
		return !$.cookie(key);
	};
}));