leaflet地图叠加瓦片图层

let url = 'http://gis.rwworks.com:6080/arcgis/rest/services/danjiangkou/tudizhengshouxian/MapServer';

 const testLayer = L.esri.tiledMapLayer({
      url: url,
      opacity: 1
  })
  testLayer.setZIndex(999);
 
  this.map.addLayer(testLayer);