Javascript 面试总结
Web 面试题https://blog.youkuaiyun.com/ttu1evldelfq5btqik/article/details/79366731
- 基本类型
typeof(Number)
"function"
typeof(NULL)
"undefined"
typeof(undefined)
"undefined"
typeof(Undefined)
"undefined"
typeof(Boolean)
"function"
typeof(String)
"function" JavaScript 如何判断一个obj 是不是数组
var obj=[1,2,3]
undefined
obj
(3) [1, 2, 3]
Object.prototype.toString.call(obj)
"[object Array]"