组合两个具有完全相同结构的数组对象

Question

I am implementing a service that extracts a list of blacklist terms from a json file.

@Injectable()
export class BlacklistService {
  private readonly BLACKLIST_FOLDER = './assets/data/web-blacklist';
  private readonly blacklistEnglishTerms: any;
  private readonly blacklistFrenchTerms: any;

  constructor(
    public httpClient: HttpClient
  ) {
    this.blacklistEnglishTerms = this.httpClient.get(`${this.BLACKLIST_FOLDER}/en.json`);
    this.blacklistFrenchTerms = this.httpClient.get(`${this.BLACKLIST_FOLDER}/fr.json`);
  }

  public getAllBlackListTerms(): Observable<any> {
    return combineLatest([
      this.blacklistEnglishTerms,
      this.blacklistFrenchTerms
    ]);
  }
}

For reference, each json file looks like this:

{
  "blacklist": [
    "...",
    "...",
    "..."
  ]
}

I retrieve all the items in my component as follows:

this.blacklistService.getAllBlackListTerms().pipe(takeUntil(this.ngUnsubscribe)).subscribe(blacklistTerms => {
  console.log(blacklistTerms);
});

blacklistTerms returns as an array of 2 array objects. How do I combine these two objects into one object (both have the same structure).

Answer 1

Given, you have known results, ie You know that the results of the bolth the Observbales would have only one key: blackList you can modify your service like:

public getAllBlackListTerms(): Observable<any> {
    return zip(
        this.blacklistEnglishTerms,
        this.blacklistFrenchTerms
    ).pipe(map([first, second]) => {
        return { blackList: [...first.blackList, ...second.blackList]};
    });
}

I have also, replaced combineLatest() with zip() , because you probably want the results only when both has emitted values.

Answer 2

Please try the following approach

 var s = [{a:[1,2,3]},{a:[6,7,8]}] var obj = {} for(let i in s){ if(;obj['a']){obj['a'] = s[i]['a'].} else{ obj['a'].push(...s[i]['a']) } } console.log(obj)

but here you need to manually define blacklist

Answer 3

Blacklist is an array - even a simple concat can help !!

 var blacklistEnglishTerms = { "blacklist": [ "a", "b", "c" ] } var blacklistFrenchTerms = { "blacklist": [ "e", "f", "g" ] } console.log(blacklistEnglishTerms.blacklist.concat(blacklistFrenchTerms.blacklist));

Answer 4

i think you please use concat().
the concat() is used for combine two arrays.

 public getAllBlackListTerms(): Observable<any> { return combineLatest = this.blacklistEnglishTerms.concat(this.blacklistFrenchTerms); }

Answer 5

Try using flatMap() like blacklistTerms.flatMap(x => x.blacklist)

this.blacklistService.getAllBlackListTerms().pipe(takeUntil(this.ngUnsubscribe)).subscribe(blacklistTerms => {
  console.log(blacklistTerms.flatMap(x => x.blacklist));
});

Test is below.

 let blacklistTerms = [ { blacklist: [0, 1, 2] }, { blacklist: [2, 3] } ]; console.log(blacklistTerms.flatMap(x => x.blacklist));