jquery.cookie.js的介绍与使用方法
什么是 cookie?
cookie 就是页面用来保存信息,比如自动登录、记住用户名等等。
cookie 的特点
- 同个网站中所有的页面共享一套 cookie
- cookie 有数量、大小限制
- cookie 有过期时间jquery.cookie.js 是一款轻量级的 cookie 插件,可以读取,写入和删除 cookie。本文主要针对
jquery.cookie.js 的用法进行详细的介绍。
使用方法:
设置 cookie:
$.cookie('the_cookie', 'the_value'); |
注:如果 $.cookie
没有第三个参数,那么当浏览器关闭时,该 cookie 将会自动删除。
设置一个有效期为 7 天的 cookie:
$.cookie('the_cookie', 'the_value', {expires: 7}); |
注:$.cookie
第三个参数是一个对象,除了可以设置有效期(expires: 7
),还可以设置有效路径(path: '/'
)、有效域(domain: 'jquery.com'
)及安全性(secure: true
)。
读取 cookie:
$.cookie('the_cookie'); |
注:如果没有该 cookie,返回 null。
删除 cookie:
$.cookie('the_cookie', null); |
我们只需要给需要删除的 cookie 设置为 null,就可以删除该 cookie。
最后附上源代码:
/** * Cookie plugin * * Copyright (c) 2006 Klaus Hartl (stilbuero.de) * Dual licensed under the MIT and GPL licenses: * http://www.opensource.org/licenses/mit-license.php * http://www.gnu.org/licenses/gpl.html * */ /** * Create a cookie with the given name and value and other optional parameters. * * @example $.cookie('the_cookie', 'the_value'); * @desc Set the value of a cookie. * @example $.cookie('the_cookie', 'the_value', { expires: 7, path: '/', domain: 'jquery.com', secure: true }); * @desc Create a cookie with all available options. * @example $.cookie('the_cookie', 'the_value'); * @desc Create a session cookie. * @example $.cookie('the_cookie', null); * @desc Delete a cookie by passing null as value. Keep in mind that you have to use the same path and domain * used when the cookie was set. * * @param String name The name of the cookie. * @param String value The value of the cookie. * @param Object options An object literal containing key/value pairs to provide optional cookie attributes. * @option Number|Date expires Either an integer specifying the expiration date from now on in days or a Date object. * If a negative value is specified (e.g. a date in the past), the cookie will be deleted. * If set to null or omitted, the cookie will be a session cookie and will not be retained * when the the browser exits. * @option String path The value of the path atribute of the cookie (default: path of page that created the cookie). * @option String domain The value of the domain attribute of the cookie (default: domain of page that created the cookie). * @option Boolean secure If true, the secure attribute of the cookie will be set and the cookie transmission will * require a secure protocol (like HTTPS). * @type undefined * * @name $.cookie * @cat Plugins/Cookie * @author Klaus Hartl/klaus.hartl@stilbuero.de */ /** * Get the value of a cookie with the given name. * * @example $.cookie('the_cookie'); * @desc Get the value of a cookie. * * @param String name The name of the cookie. * @return The value of the cookie. * @type String * * @name $.cookie * @cat Plugins/Cookie * @author Klaus Hartl/klaus.hartl@stilbuero.de */ jQuery.cookie = function(name, value, options) { if (typeof value != 'undefined') { // name and value given, set cookie options = options || {}; if (value === null) { value = ''; options = $.extend({}, options); // clone object since it's unexpected behavior if the expired property were changed 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 } // NOTE Needed to parenthesize options.path and options.domain // in the following expressions, otherwise they evaluate to undefined // in the packed version for some reason... 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; } }; |
总结
以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作能带来一定的帮助,如果有疑问大家可以留言交流。