How do I define an interface in TypeScript?

How do I define an interface in TypeScript?

In TypeScript, you can define an interface using the interface keyword. For example:

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

Can you give me an example of how to use that interface?

Sure! You can use the Person interface like this:

const john: Person = {
    name: 'John Doe',
    age: 30
};

What if I want to add optional properties?

You can add optional properties by using a question mark ?. For example:

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

How do I implement this interface in a class?

You can implement an interface in a class using the implements keyword. For example:

class Employee implements Person {
    name: string;
    age: number;
    email?: string;

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