Learn TypeScript

TypeScript Topics

Click on a topic to expand and learn in detail.

• 1. Introduction to TypeScript

let message: string = "Hello, TypeScript!";
console.log(message);
      

TypeScript is a superset of JavaScript with static typing, making code more robust.

• 2. Variables & Types

let name: string = "Alice";
let age: number = 25;
let isStudent: boolean = true;
let scores: number[] = [90, 85, 78];
      

TypeScript allows defining types for variables, arrays, objects, etc.

• 3. Functions

function add(a: number, b: number): number {
    return a + b;
}
console.log(add(5, 3));
      

Functions in TypeScript have typed parameters and return types.

• 4. Objects & Interfaces

interface Person {
  name: string;
  age: number;
}

let p: Person = { name: "Alice", age: 25 };
console.log(p.name);
      

Interfaces define the structure of objects for type safety.

• 5. Classes & OOP

class Student {
  name: string;
  age: number;

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

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

let s = new Student("Alice", 25);
s.greet();
      

TypeScript supports full object-oriented programming with classes and inheritance.

• 6. Generics

function identity(arg: T): T {
    return arg;
}

console.log(identity(5));
console.log(identity("Hello"));
      

Generics allow writing reusable, type-safe functions and classes.

• 7. Advanced TypeScript
• Type Aliases & Union Types
• Enums
• Modules & Namespaces
• Decorators
• Async/Await with Typed Promises

// Enum example
enum Color { Red, Green, Blue }
let c: Color = Color.Green;

// Union type
let val: string | number = "Hello";
val = 42;