js中的typeof和instanceof的区别

1.typeof以字符串的形式返回类型，具体有6种类型：number,boolean,string,function,object,undefined　　

typeof(1): number
typeof(NaN): number
typeof(Number.MIN_VALUE): number
typeof(Infinity): number
typeof("123"): string
typeof(true): boolean
typeof(window): object
typeof(Array()): object
typeof(function(){}): function
typeof(document): object
typeof(null): object
typeof(eval): function
typeof(Date): function
typeof(sss): undefined
typeof(undefined): undefined

2.instanceof用来判断对象是否是某个类的实例,返回值为true或者false

var a = new Array();

alert(a instanceof Object);//true;

alert(window instanceof Object);//高版本的浏览器返回true,以前的返回false