Tips for utilizing the incoming variable data from the subscription in Angular when making API calls outside of the subscribing method

I am encountering an issue in my Angular application where I am unable to access a variable outside of the subscription block after calling an API in a service and subscribing to the data in a component.

.service.ts

dronedetails():Observable<object>{
  let httpOptions = {
    headers: new HttpHeaders({
    'Content-Type': 'application/json',
      'Authorization': 'Token ' + localStorage.getItem('token')
    })
  };
 
    return this.http.get(environment.apiUrl +'/api/data/json', httpOptions)

After subscribing to the data in the component:

.component.ts

 ngOnInit() {

this.ds.dronedetails()
       .subscribe((drones)=>{
         this.drones = drones;

      console.log('obj',drones);
       },
       err=>{
        console.log("Error",err)
      }
       );
//Attempting to use 'drones' outside of the subscription block does not work

var latlngs = this.drones.drone1.Drone.latlong;
    var droneid = this.drones.drone1.Drone.Droneid;

}

If anyone has a solution for this, I would greatly appreciate the help.

Answer №1

When working with subscriptions, it's important to remember that the content is executed asynchronously. This means that any actions you want to perform with the information retrieved from your API must be done inside the subscription block. If you attempt to access this.drones immediately after making the API call, the variable may not have been defined yet.

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