Overlaying OneMap onto ESRI map

ChuCheuk_Yiu

How do I overlay a map(OneMap) over an ESRI map? It is possible as shown in the url below. There are many layers that can be overlaid onto the ESRI map and even OneMap basemap, what methods can I use to overlay the basemap (http://www.onemap.sg/ArcGIS/rest/services/BASEMAP/MapServer) onto ESRI map?

url: http://www.arcgis.com/home/webmap/viewer.html?useExisting=1

ManishkumarPatel

Hi Chu Cheuk Yiu,

The difference in the projection of the One Map map service and ESRI will not allow it to add as a basemap or feature layer.

Since One Map is using SVY21 projection what you can do is overlay the onemap as an ArcGISDynamicMapServiceLayer on top of the ESRI basemap. Althought if you add One Map as dynamic map service layer it will not adhere to the One Map scales and display map projection as the esri basemap projection.

Another option is that you will need to write your own custom function to handle the change of the basemaps where in you will need destroy and create the map again and then add any basemap as per requirement. In this case the map projection will adhere to the One Map projection.

map.destroy();
map = new map("mapdiv");

Hope this helps.

Regards,
Manish Patel