What are TypeScript interfaces and can you give me an example?

What are TypeScript interfaces and can you give me an example?

TypeScript interfaces are used to define the structure of an object. For example, you can define an interface for a user like this:

interface User {
    name: string;
    age: number;
    email: string;
}```
This interface ensures that any object of type User will have these three properties.

How do I implement this interface in a function?

You can use the interface as a type for function parameters. For example:

function greetUser(user: User) {
    console.log(`Hello, ${user.name}!`);
}```
This function takes a User object and greets the user by name.

Can I extend an interface in TypeScript?

Yes, you can extend interfaces in TypeScript. For example:

interface Admin extends User {
    role: string;
}```
This Admin interface now has all properties of User plus an additional role property.

What happens if I don't implement all properties of an interface?

If you don't implement all properties of an interface, TypeScript will throw a compilation error, ensuring type safety.