问如何去除掉落的地图标记？

EN

public AddMarker(){
    let image = '/assets/img/rsz_marker.png';   
    let marker = new google.maps.Marker({    
    map: this.map,
    animation: google.maps.Animation.DROP,
    position: this.map.getCenter()
    , icon: image
  }); 
  }
    platform.registerBackButtonAction(() => {
      if (this.nav.canGoBack()) {
        this.nav.pop();
      } else {
         //*remove marker?
      }
    });