我想访问位于component.ts中的更新变量，并将其分配给方法外的其他变量。

Question

service.ts

get_update(id:any): Observable<any[]>{
    let headers = new Headers({ 'Content-Type': 'application/json'});
    let options = new RequestOptions({ headers: headers });
    return this.http.get('http://localhost:8000/vendor/'+id,options)
                        .map((res: Response) =>  res.json())
                        .catch(error => Observable.throw(error.statusText));
}

component.ts

this.service.get_update(this.user).subscribe(update => this.update = update,
                                      error =>console.log(error));

I want to access the update variable which is in component.ts and i want to assign it to other variable outside the method.How to do it

Answer 1

Accessing this.update in some other method will not help as the value is getting assigned inside a callback and some other method will not wait for its execution resulting in null value. Either you can have a function callback as an input for get_update method, such that when you get update value you can pass that value to the respective callback or you can directly call the other method inside your callback passing the update value as input parameter.