设置和获取cookie

function setCookie(name,value){

document.cookie = name + "=" + encodeURI(value);

}

function getCookie(name){

var str = document.cookie;

if(!str || str.indexOf(name + "=") < 0){

return null;

}

var cookies = str.split(";");

for(var i=0; i < cookies.length; i++){

var cookie = cookies[i];

if(cookie.indexOf(name + "=") == 0){

var value = cookie.substring(name.length + 1);

return decodeURI(value);

}

}

return null;

}