Using Enums and Literal Types

TypeScript is nothing if not chock-full of many different ways to specify a type that is limited to a few values. We’ve just looked at literal types, but those are effectively just a subset of what you can do in TypeScript using an enumerated type, or enum.

Defining enums

TypeScript enums are very flexible and allow you to do a lot of things that seem, frankly, to be rather pointless. I’ll try to minimize talking about those.

At the simplest, you can define an enum in TypeScript just by providing a list of values for it. So, if we wanted to convert our TicketStatus type to an enum, we could do this:

enum TicketStatus {Unsold, Held, Purchased, Refunded, Invalid}

Which we can then use as ...