检测类型

typeof

var s = "Nicholas";

var b =true;

var i =22;

var u;

var n =null;

var o =new Object();

alert(typeof s);  //string

alert(typeof i);  //number

alert(typeof b);  //boolean

alert(typeof u);  //undefined

alert(typeof n);  //object

alert(typeof o);  //object

instanceof

alert(person instanceof Object);  //变量person是Object吗？

alert(colors instanceof Array);  //变了colors是Array吗？

检测类型

原文：http://liuxinyun.blog.51cto.com/8263686/1895632