cookie函数的封装

增加/修改cookie：

function setCookie(name,value,iDay){
    var newDate = new Date();
    newDate.setDate(newDate.getDate()+iDay);
    document.cookie=name+"="+value+";expires="+newDate+";path=/";
}

获取cookie函数：

function getCookie(name){     
    let cookie = document.cookie;
    var arr = cookie.split("; ");
    for(var i =0; i<arr.length; i++){
        var arr2 = arr[i].split("=");
        if(arr2[0] == name){
            return arr2[1];
        }
    }
}

删除cookie函数（搭配增改函数使用）：

function removeCookie(name){
      setCookie(name,1,-100);
}