Why You Should Use Type Instead of Interface in TypeScript

TypeScript provides two main ways to define the shape of an object: type and interface. While both can be used interchangeably in many cases, there are specific scenarios where type offers more flexibility and power. This blog will explore these scenarios and explain why you might prefer type over interface.

Key Differences:

1. Union Types

type can define union types, which an interface cannot.

2. Intersection Types

type can define intersection types.

3. Primitive Types

type can alias primitive types.

4. Tuples

type can define tuples

5. Mapped Types

type can create mapped types

6. Complex Type Constructs

type can define more complex type constructs like conditional types.

Let's consider a React component where we define the props using type instead of interface.

7. Union Types in React component

8. Intersection Types in React component

When you need to combine multiple types, the type is more flexible.

9. Tuples in React component

When you need to define a tuple type, type is the only option.

Using interface (Not Possible)

10. Mapped Types in React component

When you need to create a mapped type, type is more suitable.

Using interface (Not Possible)

Conclusion

While interface is useful for defining object shapes that are intended to be extended or implemented by classes, type offers more versatility and power for defining complex types. By understanding the type's strengths, you can make more informed decisions in your TypeScript projects.

In summary, use type when you need:

This flexibility makes type a better choice in many scenarios.