topic Re: "QueryTask" at 100.x in .NET Maps SDK Questions

"QueryTask" at 100.x

MarkCederholm — Tue, 15 Aug 2017 22:36:03 GMT

Is there anything like the QueryTask/FindTask/IdentifyTask classes at 100.x? Or in the works? I can create a ServiceFeatureTable just fine from a map image service and query that, but there are times when the 10.2.x classes come in real handy.

Re: "QueryTask" at 100.x

MarkCederholm — Thu, 17 Aug 2017 15:53:21 GMT

Also, is there a way to retrieve something like a ArcGISMapImageSublayer info for tables in a map image service? IdInfos don't cut the mustard, and hydrating a ServiceFeatureTable is a serious performance hit. I really hate the thought of wrapping the REST API in my own classes when 10.2.x does it so conveniently.

Re: "QueryTask" at 100.x

MarkCederholm — Sun, 12 Dec 2021 03:13:59 GMT

          private static ArcGISMapServiceSublayerInfo GetInfoFromUrl(string sServiceUrl, long iSubLayerID)
          {

               // Create sublayer info from JSON

               string sLayerUrl = sServiceUrl + "/" + iSubLayerID.ToString();
               string sRequest = sLayerUrl + "?f=json";
               HttpWebRequest r = (HttpWebRequest)WebRequest.Create(sRequest);
               r.UseDefaultCredentials = true;
               r.PreAuthenticate = true;
               r.Credentials = CredentialCache.DefaultCredentials;
               HttpWebResponse result = (HttpWebResponse) r.GetResponse();
               string sJSON;
               using (StreamReader sr = new StreamReader(result.GetResponseStream()))
               {
                    sJSON = sr.ReadToEnd();
               }
               ArcGISMapServiceSublayerInfo info = ArcGISMapServiceSublayerInfo.FromJson(sJSON);
               return info;

          }
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Re: "QueryTask" at 100.x

MarkCederholm — Tue, 22 Aug 2017 18:28:09 GMT

Thank goodness for JavaScriptSerializer! Life is easier now.

Re: "QueryTask" at 100.x

JoeHershman — Tue, 22 Aug 2017 19:05:52 GMT

Why not json.net?

Re: "QueryTask" at 100.x

MarkCederholm — Tue, 22 Aug 2017 19:21:44 GMT

No real reason -- it's a good library. I just don't like the dependency. Same reason I avoid MVVM Light and stick to System.Windows.Interactivity.

Re: "QueryTask" at 100.x

dotMorten_esri — Wed, 23 Aug 2017 18:23:52 GMT

There is no FindTask at the moment.

IdentifyTask has been replaced with the Identify methods directly on the GeoView should should make creating idenfy across many layers much much easier.

QueryTask has been replaced with query against a ServiceFeatureTable.

Re: "QueryTask" at 100.x

MarkCederholm — Wed, 23 Aug 2017 19:15:15 GMT

Thanks for the info. Are ServiceFeatureTables limited by maxRecordCount, or do they work around it by querying IDs first? Also, a unique values method would be very useful.

Re: "QueryTask" at 100.x

dotMorten_esri — Wed, 23 Aug 2017 19:54:04 GMT

They are currently limited by maxRecordCount. Paging and Statistics Queries are scheduled to be coming in the next update.

You can get around maxRecordCount by repeating the query and add "WHERE ObjectID > [HighestOIDSoFar"

Re: "QueryTask" at 100.x

MarkCederholm — Thu, 24 Aug 2017 19:40:06 GMT

The GeoView identify methods are a good start, but limited in that they only allow a screen point and tolerance. Ideally, general geometry types should be supported.

Re: "QueryTask" at 100.x

dotMorten_esri — Thu, 24 Aug 2017 19:48:49 GMT

I think what you are asking for then is spatial queries. That's a very different operation than identify.

Identify runs at the pixel level and intersects the _symbol_ being rendered, not the geometry (although there are some exceptions for services not supporting that). The old identify task was actually no different, as the ArcGIS Server Rest Endpoint works the exact same way in pixel-coordinate space.

Re: "QueryTask" at 100.x

MarkCederholm — Thu, 24 Aug 2017 19:55:26 GMT

Not true! The REST Map service identify operation works with a general geometry. And it's a much more efficient operation than querying individual sublayers.

http://resources.arcgis.com/en/help/arcgis-rest-api/index.html#/Identify_Map_Service/02r300000113000000/

also:

https://developers.arcgis.com/net/10-2/desktop/api-reference//html/T_Esri_ArcGISRuntime_Tasks_Query_IdentifyParameters.htm

Re: "QueryTask" at 100.x

dotMorten_esri — Thu, 24 Aug 2017 20:03:36 GMT

Yes and no. There's a reason extent and screen size are required parameters. But fair enough... you can use more advanced geometry than a single-point + tolerance

Re: "QueryTask" at 100.x

brysageek — Fri, 11 Mar 2022 22:45:26 GMT

Let me start off by saying great job on the new runtime, love many of the design choices of the 100.x, buuuuutttt I do see many use cases for needing to query a service directly--there are some services that we like to query without having them added to the GeoView, the ServiceFeatureTable query features has gotten me pretty far with updating apps from the old WPF but now I am attempting to do the same yet with ImageServices... not seeing anything similiar to queryfeatures from ServiceFeatureTable/ArcGISFeatureTable on the ImageServiceRaster or base Raster. -am I missing something? Is this up and coming ? Do I need to implement my own, noticing ImageSeviceRaster and Raster are sealed.