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Data.query$<T>(...)

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With dnn-sxc-angular it's really easy to access Data from the backend.

The easiest way to access a Query is to use data.query$<T>(...) which gets you a Stream ($) of Entities from a Query.

Here's what it does:

  • data.query$<T>(...) will get you...
  • ...an observable of T
  • you'll usually use <YourType[]> since you'll get an array back
  • the Query name is specified in the ('BusinessUnitTeam')

Example

We'll explain how to run a query based on the Template App.

Check out the team.service.ts - you'll see some code like this:

@Injectable({
  providedIn: 'any',
})
export class TeamService {
  /** This will contain the persons returned from the API */
  team$: Observable<Person[]>;

  constructor(data: Data, context: Context) {
    this.team$ = data.query$<Person[]>(`BusinessUnitTeam?bu=Web`);
  }
}

The important line is this:

this.team$ = data.query$<Person[]>(`BusinessUnitTeam?bu=Web`);

This will query the BusinessUnitTeam Query on the backend with parameter bu being Web (to only get members of the Web-team). Here's what it does

  1. We're using the Data object provided by dnn-sxc-angular
  2. The query$<T>(...) requests an observable stream of BusinessUnit[] objects
  3. The term ...('BusinessUnitTeam') is the name of the query
  4. The additional parameters like ?bu=Web is expected by the query (in this case the query could also accept an empty BU)

Other overloads

The query$<T>(...) has various other overloads to include parameters. You'll see them in the intellisense in VS Code.

Difference to Data.query<T>(...)

The Data object also has a query<T>(...) without the $. That doesn't return a stream/observable of data, but instead returns a Query object which can be used for multiple calls. As of now it's probably not very usefull, so let's stick to this.

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