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输出什么?

javascript
class Person {
  constructor(name) {
    this.name = name
  }
}

const member = new Person("John")
console.log(typeof member)

A. "class" B. "function" C. "object" D. "string"

答案: C

解析:

类是构造函数的语法糖,如果用构造函数的方式来重写Person类则将是:

javascript
function Person() {
  this.name = name
}

通过new来调用构造函数,将会生成构造函数Person的实例,对实例执行typeof关键字将返回"object",上述情况打印出"object"