js this有哪些属性

console.log(this); // 在浏览器中输出: Window {...}

function showThis() {
  console.log(this);
}

showThis(); // 非严格模式下输出: Window {...}

function showThisStrict() {
  'use strict';
  console.log(this);
}

showThisStrict(); // 输出: undefined

const obj = {
  name: 'Alice',
  greet: function() {
    console.log(`Hello, ${this.name}`);
  }
};

obj.greet(); // 输出: Hello, Alice

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

const alice = new Person('Alice');
console.log(alice.name); // 输出: Alice

<button id="myButton">Click me</button>

<script>
document.getElementById('myButton').addEventListener('click', function() {
  console.log(this); // 输出: <button id="myButton">Click me</button>
});
</script>

const obj = {
  name: 'Alice',
  greet: function() {
    setTimeout(() => {
      console.log(`Hello, ${this.name}`);
    }, 100);
  }
};

obj.greet(); // 输出: Hello, Alice

function greet() {
  console.log(`Hello, ${this.name}`);
}

const person = { name: 'Alice' };

greet.call(person); // 输出: Hello, Alice
greet.apply(person); // 输出: Hello, Alice

const greetPerson = greet.bind(person);
greetPerson(); // 输出: Hello, Alice

const obj = {
  name: 'Alice',
  greet: function() {
    setTimeout(function() {
      console.log(`Hello, ${this.name}`);
    }.bind(this), 100); // 使用 bind 绑定 this
  }
};

obj.greet(); // 输出: Hello, Alice

function Person(name) {
  if (!(this instanceof Person)) {
    return new Person(name);
  }
  this.name = name;
}

const alice = Person('Alice'); // 自动使用 new 调用
console.log(alice.name); // 输出: Alice