JS操作cookie的实现

var Cookie = {
    set:function (key,val,expiresDays) {
        if(expiresDays){
            var date = new Date();
            date.setTime(date.getTime()+expiresDays*24*3600*1000);//格式化时间
            var expiresStr = "expires="+date.toGMTString()+';';
        }else{
            var expiresStr = '';
        }
        document.cookie = key+'='+encodeURI(val)+';'+expiresStr;
    },
    get:function (key) {
        var getCookie = document.cookie.replace(/[ ]/g,'');
        var resArr = getCookie.split(';');
        var res;
        for(var i=0,len=resArr.length;i<len;i++){
            var arr = resArr[i].split('=');
            if(arr[0]==key){
                res = arr[1];
                break;
            }
        }
        return decodeURI(res);
    }
};