How to pass an array within a query string in HttpClient?

Question

This is my array of actors:

['Elvis', 'Jane', 'Frances']

How to pass this array within a query string in HttpClient?

I tried to use:

1)

let params = new HttpParams();
params = Params.append('actors[]', ['Elvis', 'Jane', 'Frances']);
this.http.get(url, { params: Params });

let params = new HttpParams().set('actors[]', ['Elvis', 'Jane', 'Frances']);
this.http.get(url, { params: Params });

let Params = new HttpParams();
Params = Params.append('actors[]', 'Jane');
Params = Params.append('actors[]', 'Elvis');
Params = Params.append('actors[]', 'Frances');
this.http.get(url, { params: Params }); 

1st and 2nd snippets don't work because of TypeScript error:

[ts] Argument of type 'string[]' is not assignable to parameter of type 'string'.

3rd snippet sends only one item 'actors[]': 'Frances'

Answer 1

I think the best way is to add them to parameters as a string and have your back-end convert it back to an array or list.

let actorList = ['Elvis', 'Jane', 'Frances']
let params = new HttpParams();
params = params.append('actors', actorList.join(', '));
this.http.get(url, { params: params });