instanceof

instanceof运算符用于测试构造函数的prototype属性是否出现在对象的原型链中的任何位置

 

function Car(make, model, year) {
  this.make = make;
  this.model = model;
  this.year = year;
}
var auto = new Car('Honda', 'Accord', 1998);

console.log(auto instanceof Car);
// expected output: true

console.log(auto instanceof Object);
// expected output: true

 

object

要检测的对象.

constructor

某个构造函数