Select Features from ArcGISDynamicMapServiceLayer without use of GraphicsLayer?

[markcheyne]

Say that I have an attribute query to select a single feature from a dynamic layer, and I want it to draw in a 'selected' state, like with a cyan selection color.

I'm familiar with using a QueryTask to perform the attribute query, getting the geometry and displaying it in a separate GraphicsLayer, with whatever symbol I specify.

The problem is this - the selected feature's geometry could be very large - picture a 300-mile long meandering double-line river at 1:24K scale. It could be several megabytes when serialized to JSON. It seems wasteful of bandwidth, time, and RAM to push that geometry to the client simply so it can be lit up in a selected state.

What I hope for is a REST API request that produces a map image like normal, but with the server rendering the specified feature in a selected state.

I think I know this is not an option, but worth asking in case I'm missing something.

Thanks!

[DaveTimmins]

You can do this with ArcGIS Server 10.1 through dynamic query layers. There is an example on the Interactive SDK http://resources.arcgis.com/en/help/silverlight-api/samples/start.htm#DynamicLayerThematic. REST API documentation at http://resources.arcgis.com/en/help/rest/apiref/dynamicLayer.html

Cheers,

[wangzhifang]

Just as Dave said, remember a simple priciple, when you feel the response size is too large to process it on client side, then consider to let server side done the job:) Or, replace your original need.