JS拿cookie值

/*
* name 是cookie的名字,value是cookie的值 days表示保存几天
*/
function createCookie(name,value,days){
if(days){
var date = new Date();
date.setTime(date.getTime()+(days*24*60*60*1000));
var expires ='; expires=' +date.toGMTString();
}else{
var expires ='';
}
document.cookie = name+'='+value+expires+'; path=/';
}

//取出name为name的value值
function readCookie(name){
var nameEQ = name+'=';
var ca = document.cookie.split(';');//其实可以用'; '分隔

for(var i=0;i<ca.length;i++){
var c = ca[i];
while(c.chatAt(0)==' ') s.substring(1,c.length);
if(c.indexOf(nameEQ)==0) return s.substring(nameEQ.length,c.length);
}
return '';
}

function eraseCookie(name){
createCookie(name,'',-1);
}