js文件Cookie存取值示例代码

/* 
Cookie工具 
使用方法: 
//存值 
var value = "7天"; 
tools.cookie("day",value, {expires:7}); //将字符串:"7天" 以 "day"这个key保存到cookie中5天 
//取值 
var v = tools.cookie("day"); //用 "day" 这个key从cookie取出值 
*/ 
tools.cookie = function(name, value, options) { 
if (typeof value != 'undefined') { // name and value given, set cookie 
options = options || {}; 
if (value === null) { 
value = ''; 
options.expires = -1; 
} 
var expires = ''; 
if (options.expires 
&& (typeof options.expires == 'number' || options.expires.toGMTString)) { 
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.toGMTString(); // use expires 
// attribute, 
// max-age is not 
// supported by IE 
} 
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; 
} 
};