old

import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class DataService {
  private dataSource = new BehaviorSubject(Object);
  public currentData = this.dataSource.asObservable();

  constructor() {}

  changeData(data) {
    this.dataSource.next(data);
  }
}

new :红色部分是重点 

import { Injectable } from '@angular/core';
import { BehaviorSubject, Observable } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class DataService {
  private dataSource = new BehaviorSubject(Object);
  public currentData: Observable<Object> = this.dataSource.asObservable();

  constructor() {}

  changeData(data) {
    this.dataSource.next(data);
  }
}

问题:可观测属性的问题,

 

当我使用的是可观测的属性，但找不到它。要解决这个问题，我需要简单地添加缺少的可观察导入，并在当前数据变量中键入：然后就可以解决了