Learn Class Constructors | ES6 Class Fundamentals

When you create a new object from a class in JavaScript, you often want to set up its initial state—such as assigning values to its properties. This is where the constructor method comes in. The constructor is a special method inside a class definition that is automatically called when you use the new keyword to create an instance of the class. You can use it to set up the properties of the object with specific values, usually by passing arguments to the constructor when creating the object.


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

const user = new Person("Alice", 30);
console.log(user.name); // "Alice"
console.log(user.age); // 30

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Section 1. Chapter 4

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              12345678910
            
class Person {
  constructor(name, age) {
    this.name = name;
    this.age = age;
  }
}

const user = new Person("Alice", 30);
console.log(user.name); // "Alice"
console.log(user.age); // 30

Everything was clear?

Thanks for your feedback!

Section 1. Chapter 4