do I have to change spatial reference for map services for identify?

Question

I need to do identify for my map service layers and online editing for feature layers. both of map service and feature service are generated from a same MXD with spatial reference of Texas south centra. I use ESRI basenmap as background of my map. I can do online editing with no problem. But my mapservice layers and feature service layers failed to identify. Can Feature layer be identified? What should be done for identify without affect editing? Do I have to convert it to  WKID="4326"  in MXD file for my map services layers and feature services?

DominiqueBroux · Answer

The trick is to initialize the spatialreference property of the IdentifyParameters.
Something like: 
ESRI.ArcGIS.Client.Tasks.IdentifyParameters identifyParams = new IdentifyParameters()
{
Geometry = clickPoint,
MapExtent = map.Extent,
Width = (int)map.ActualWidth,
Height = (int)map.ActualHeight,
LayerOption = LayerOption.visible,
SpatialReference = map.SpatialReference
};

JenniferNery · Answer

The MapService need not match the Map's SpatialReference.  In the SDK sample: http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#Identify, the base layer where map inherits its SpatialReference from belong to 4326 and the MapService belong to 4269. Here's a link to IdentifyParameters documentation: http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.Tasks.IdentifyParameters.html  Have you tried reproducing the issue outside the SL app?  Did you find any difference in the web browser result?  Were the parameters correct?

XiujuZhou · Answer

My question is whether different spatial references between esri map and my map can cause identify no result? I mean, are different spatial references OK when my layers need to be identified?To test if IdentifyTask failed in your SL application or if empty IdentifyResults was expected, you can use Fidder to see what parameters SL app formed and use the same parameters in your web browser. If the result that you get from the web browser is not identical to the result you get from your application, we may have a problem.  To do this, you can look at this thread, post #14 http://forums.arcgis.com/threads/14730-Area-And-Perimeter.