ngrx actions with optional payload

Question

I'm working with Angular 8 and NgRx 8, is it possible create an action with optional payload? I'm trying to do something like:

export const MyAction = createAction('[Action ] MyAction', props<{ prop?: string }>());

but unfortunately doesn't work. Could you help me?

Answer 1

Based on this post there is an optional payload definition.

Example:

export const FetchPlayersAction = createAction(
  '[Players.List] FETCH_PLAYERS',
  (payload: ListingOptions = {}) => payload, // defined optional payload
);

Answer 2

Based on your example, you can set a default value, and then it's optional:

export const MyAction = createAction(
  '[Action ] MyAction',
  (prop: string = 'My default value') => ({ prop })
);