js isNaN()函数 

alert (isNaN("asdas"));//返回true
alert (isNaN(""));//返回false
alert (isNaN());//返回true
alert (isNaN(2));//返回false
alert (isNaN("2"));//返回false
posted @ 2020-04-14 13:24  KwFruit  阅读(109)  评论(0)  编辑  收藏  举报