单击 angular 8 滚动到页面顶部

Question

I have angular 8 application.

And I have navigation buttons for next and previous. But so I want to archieve that you will be navigate to top of the page when next is triggerd.

So I have this:

 <h4 id="heading"  #goUp class="echeq-title">{{ currentEcheqPage.title }}</h4>

and ts file:

export class EcheqPageComponent implements OnInit, AfterViewInit {

  @Input() currentEcheqPage: EcheqPage;
  @Input() currentEcheqPager: EcheqPager;
  @ViewChild('goUp', {static: false}) contentPage: ElementRef;

  // We use template variables to query the components
  @ViewChildren('echeqElement') elementComponents: QueryList<EcheqElementComponent>;

  EcheqElement = EcheqElement;
  elementsChanged = true;
  container: HTMLElement;

  constructor( private echeqService: EcheqService ) { }

  ngOnInit() {
    // document.getElementById ('heading').scrollIntoView();
  }

  ngAfterViewInit(): void { 
    this.showUp();

  }
}

private showUp(): void {
    this.contentPage.nativeElement.scrollTo( 0, 0 );
  }

But I don't get error. But also it is not navigating to top of page. IN this case the h4 heading.

So what I have to change?

Thank you.

Answer 1

This is the solution:

  @ViewChild('goUp', { static: true }) contentPage: ElementRef;

 ngOnChanges(): void {
   this.showUp();
  }

  showUp() {
     this.contentPage.nativeElement.scrollIntoView();
  }

Answer 2

The document object in typescript/javascript, has a function called "scrollIntoView", which can be used to scroll to a specific element. In your case you could created a functions as seen on the snippet below:

showUp() {
    const element = document.querySelector('#goUp');
    element.scrollIntoView();
}

Hope that was helpful to you. :-)

Answer 3

If I understand you correctly, change the following section:

 private showUp(): void {
    window.scroll(0,0);
  }