封装 Cookie 方法
function setCookie(cname,cvalue,exdays){
var d = new Date();
d.setTime(d.getTime()+(exdays*24*60*60*1000));
var expires = "expires="+d.toGMTString();
document.cookie = cname+"="+cvalue+"; "+expires;
}
function getCookie(cname){
var name = cname + "=";
var ca = document.cookie.split(';');
for(var i=0; i<ca.length; i++) {
var c = ca[i].trim();
if (c.indexOf(name)==0) { return c.substring(name.length,c.length); }
}
return "";
}
操作 Cookie
getCookie("username");
var user = getCookie("username");
if (user!="" && user!=null){
setCookie("username",user,30);
}
- 清除
删除 cookie 非常简单。您只需要设置 expires 参数为以前的时间即可,例如:你设置Cookie有效时间30,删除是只需要为-31、-40都可以
var user=getCookie("username");
if (user !='' && user!=null){
setCookie("username","",-40);
}