js chrome 获取对象

let obj = {
    name: "John",
    age: 30
};

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

let person = new Person("John", 30);

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

Person.prototype.greet = function() {
    console.log(`Hello, my name is ${this.name}`);
};

let person = new Person("John", 30);
person.greet();

let element = document.getElementById("myElement");

let user = {
    profile: {
        name: "John"
    }
};

console.log(user?.profile?.name); // "John"
console.log(user?.address?.city); // undefined，不会报错

let element = document.getElementById("myElement");
if (element) {
    // 元素存在时的操作
} else {
    console.log("Element not found");
}

// 对象字面量
let obj = {
    name: "John",
    age: 30
};

console.log(obj.name); // "John"

// 构造函数
function Person(name, age) {
    this.name = name;
    this.age = age;
}

let person = new Person("John", 30);
console.log(person.name); // "John"

// 原型链
Person.prototype.greet = function() {
    console.log(`Hello, my name is ${this.name}`);
};

person.greet(); // "Hello, my name is John"

// DOM 元素
let element = document.getElementById("myElement");
if (element) {
    element.textContent = "New Text";
} else {
    console.log("Element not found");
}