获取调用当前对象的对象

function myFunction() {
  console.log(this); // 输出全局对象（window）
}

myFunction();

var obj = {
  name: 'John',
  sayHello: function() {
    console.log(this.name); // 输出对象的name属性值
  }
};

obj.sayHello();

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

var person = new Person('John');
console.log(person.name); // 输出'John'

function sayHello() {
  console.log(this.name);
}

var obj1 = { name: 'John' };
var obj2 = { name: 'Jane' };

sayHello.call(obj1); // 输出'John'
sayHello.apply(obj2); // 输出'Jane'