//初始化

var imageryLayers = viewer.imageryLayers;

1.UrlTemplateImageryProvider

支持加载天地图，google，高德地图等

var _TileLayer = new Cesium.UrlTemplateImageryProvider({

            url:option.url

          });          

imageryLayers.addImageryProvider(_TileLayer)

2.ArcGisMapServerImageryProvider

var _TileLayer = new Cesium.ArcGisMapServerImageryProvider({

            layers:option.layerid,

            url:option.url

          });          

imageryLayers.addImageryProvider(_TileLayer)

3.加载WMTS服务

var _TileLayer = new Cesium.WebMapTileServiceImageryProvider({        

      url: option.url,//http://ip+port/arcgis/rest/services/server-name/MapServer/WMTS

      style: "default",  

      layer: option.layerid,  

      format: "image/jpeg",        

      tileMatrixSetID: "WebMapTileServiceImageryProvider"

    });

4.remove

viewer.imageryLayers.remove(_TileLayer );