在console、angular2中2次获取相同的值

var value = 10;
console.log(value); // 输出 10
console.log(value); // 再次输出 10

export class MyComponent {
  value: number = 10;
}

<p>{{ value }}</p>
<p>{{ value }}</p>

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

@Injectable()
export class MyService {
  getValue(): Observable<number> {
    return new Observable<number>(observer => {
      setTimeout(() => {
        observer.next(10);
        observer.complete();
      }, 1000);
    });
  }
}

export class MyComponent {
  value: number;

  constructor(private myService: MyService) {}

  ngOnInit() {
    this.myService.getValue().subscribe(value => {
      this.value = value;
      console.log(this.value); // 输出 10
      console.log(this.value); // 再次输出 10
    });
  }
}