Classes allow you to create structured objects with properties and methods. They are an important part of TypeScript and are widely used in frameworks like Nest.js.

Creating a Class

A class defines a blueprint for creating objects:

class User {
  name: string;
  age: number;

  constructor(name: string, age: number) {
    this.name = name;
    this.age = age;
  }
}

You can create an instance of the class:

const user = new User("Alice", 30);

Adding Methods

Classes can include methods that define behavior:

class User {
  name: string;

  constructor(name: string) {
    this.name = name;
  }

  greet(): string {
    return `Hello, ${this.name}`;
  }
}

Access Modifiers

TypeScript allows you to control access to properties:

• public: accessible everywhere (default);
• private: accessible only inside the class.

class User {
  private password: string;

  constructor(password: string) {
    this.password = password;
  }
}