Angular google maps不显示数组中的位置

Question

我正在尝试使用Angular Google地图在地图上显示放置在数组中的位置。如果我从组件和HTML中删除标记的编码，它的工作正常。所以我想这个问题应该在HTML页面中

export class MapviewComponent {
  zoom: number = 8;
  lat: number = 37.7919038;
  lng:number = -96.8651164 ;
   //Markers
   markers: marker[] = [{lat: 51.673858,lng: 7.815982},{lat: 51.373858,lng: 7.215982}] }

HTML编码

<agm-map
 [latitude]="lat"
  [longitude]="lng"
  [zoom]="zoom"
  [disableDefaultUI] = false
 [zoomControl] = "false"
 (mapClicked) = "mapClicked($event)">

  <agm-marker 
 *ngFor = "let m of  markers; let i = index"
 (markerClick) = "clickedMarker(m, i)"

  [latitude]="m.lat" 
  [longitude]="m.lng" 
  [label]="m.label"
  [markerDraggable]="m.draggable"
  (dragEnd)="markerDragEnd(m, $event)">
</agm-marker>
</agm-map>