What is the most effective method for transforming an interface into an object in TypeScript?

After using TypeScript for 1 year, I've noticed that creating objects to pass can be a bit cumbersome and manual.

In TypeScript, interfaces are used for type definitions and store all the necessary parameters. Is there a way to automatically generate an object from an interface?

For example:

export interface User {
  name: string;
  email: string;
}

I wish the following code could be automated, as currently I have to create a class with a constructor instead of directly using the interface.

user {
 name: ''/null/undefined,
 email: ''/null/undefined
}

let user: User = new User() // this will show error

However, I can easily create a new object using the following class.

export class User {
  constructor() {
    name: string;
    email: string;
  }
}

new User();

So, what do you think is better - creating a constructor class or using an interface?

Answer №1

Affirmative, it is possible to directly assign a value to the interface. If you do not require all properties defined in the interface to be assigned or instantiated, you can indicate them as optional by using the symbol ?. For instance, in the subsequent example, the email field is marked as optional and therefore the assignment of user will remain valid.

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

let person: Person = { name: 'John' };

Answer №2

It seems like there may not be a straightforward solution.

When it comes to interfaces and classes, they serve different purposes. Interfaces provide structure but do not exist at runtime. If you look at the compiled JavaScript from TypeScript, you won't find any traces of interfaces.

Interfaces only exist during compilation, not execution.

On the other hand, classes are present at runtime. Creating a new instance of a class like 'new User()' actually generates an instance in the resulting JavaScript code.

If needed, consider exploring abstract classes as an alternative depending on your specific scenario.

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