How to type enum values with TypeScript?

Question

Given a simple enum:

export enum IconNames {
  DEFAULT = 'DEFAULT',
  MOVE = 'MOVE',
  RESIZE = 'RESIZE',
  ADD = 'ADD',
  CANCEL = 'CANCEL',
  CLOSE = 'CLOSE',
}

I would like to type the name argument in the given function isTransform so I would call it only with IconNames value:

/* Tried `string` which doesn't work 
as `name` supposed to be enum's value */

const isTransform = (name: any) => [IconNames.MOVE, IconNames.RESIZE, IconNames.ADD].includes(name);

Do I have to build an interface for it? How do I use it?

How to build a type from enum values in TypeScript?

I think that this answers your question pretty nicely: https://stackoverflow.com/a/68747948/346005 — Arnaud Leymet, Aug 11 '21 at 19:36

score 2 · Accepted Answer · answered Apr 26 '20 at 08:30

2

This seems to work:

function isTransform(name: string): boolean {
  const transformValues: string[] = [IconNames.MOVE, IconNames.RESIZE, IconNames.ADD]
  return transformValues.indexOf(name) > -1
}

This works as well:

function isTransform(name: IconNames): boolean {
  const transformValues = [IconNames.MOVE, IconNames.RESIZE, IconNames.ADD]
  return transformValues.indexOf(name) > -1
}

The question here is would you be calling isTransform only with IconNames values or with a string?

answered Apr 26 '20 at 08:30

thedude

9,388
1
29
30

I updated the question, sorry, yes I want to call it with IconNames values – Dennis Vash Apr 26 '20 at 08:33
see the second example in my answer, doesn't it answer this usecase? – thedude Apr 26 '20 at 08:34

How to type enum values with TypeScript?

1 Answers1