How do I define JSON interfaces in TypeScript?

How do I define JSON interfaces in TypeScript?

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

interface User {
    id: number;
    name: string;
    email: string;
}

This defines a User interface with three properties.

Can you show me how to use this interface with a JSON object?

Sure! You can use the interface to type-check a JSON object like this:

const user: User = {
    id: 1,
    name: 'John Doe',
    email: '[email protected]'
};

This ensures that the object adheres to the User interface.

What if I have optional properties in my interface?

You can define optional properties using a question mark. For example:

interface User {
    id: number;
    name: string;
    email?: string; // email is optional
}

How can I validate a JSON object against this interface?

TypeScript doesn't perform runtime validation, but you can use libraries like ajv or zod to validate JSON objects against your interfaces.