Angular 调用 REST API 不等待数据到达

Question

我有以下代码：

export class Whatever implements OnInitn{

    prices;

     ngOnInit(){
       this.CoinPricesService.getPrices().subscribe(
           pricesFromResponse => {
             this.prices = pricesFromResponse;
              console.log('this is what I get from the api: ', this.prices);
           }
       );
       
      console.log('this is my prices class object', this.prices);
     }
}

输出是这样的：

this is my prices class object undefined

api: this is what I get from the $, $ $

如您所见，第一条消息显示在第二条消息中，第二条消息位于第一位，但未定义，显然发生的事情是代码不是在等待响应的到来，而是同步的，为什么？不是 observable.Subscribe（响应 ==> this.myVar = 响应）；打算照顾那个？我无法在我的 class 的其他地方使用数据，因为当代码到达那里时它总是未定义的，请帮助

我的服务是这样的：

@Injectable({
  providedIn: 'root'
})
export class CoinPricesService {

  private apiURl = 'https://api.forprices/blablabla';

  constructor(private http: HttpClient) { }

  getPrices(){
    return this.http.get<any>(this.apiURl);
  }
}

Answer 1

如果您有一个依赖于价格的函数，那么您可以在订阅中执行这些函数。像这样：

    export class Whatever implements OnInitn{
    
        prices;
    
         ngOnInit(){
           this.CoinPricesService.getPrices().subscribe(
               pricesFromResponse => {
                 this.prices = pricesFromResponse;
                  console.log('this is what I get from the api: ', this.prices);
                  someFunction(pricesFromResponse)
               }
           );
           
          
         }
         someFunction(prices){//use price ...} 
    }

Angular 调用 REST API 不等待数据到达

Angular call to REST API not waiting for the data to arrived

javascript

asynchronous

observable

rxjs

angular