Is this possible to create OFF line map with silverlight API?Is there is any way to store map related data in xml file instead of accessing services and use with silverlight API.
For the moment, the SL API doesn't manage off line layers out the box. But this is possible by code. This thread : http://forums.arcgis.com/threads/8774-save-layer-to-xml-file gives an example on how the graphic objects can be stored and loaded in the isolated storage (limitation : the symbols are not persisted, so it's only working well if your layer has a renderer).
