topic Re: IdentifyTask with multi Polygons as geometry input in ArcGIS JavaScript Maps SDK Questions

IdentifyTask with multi Polygons as geometry input

AdrianMarsden — Fri, 11 May 2012 14:03:05 GMT

As title really - I am trying to run an automated search. An input ref is passed to the map service - this finds existing features. It adds these as graphic layers using Find Task. If only one feature is found, this is passed to a Identify Task that searches loads of other layers. This all works for a single polygon, but not for multi polygons - The features in the original layer (the one that gets searched with the Find Task) are NOT multi polygon features polygons, but multiple records with the same reference (not my design - I'm hacking into another system)

Any ideas?

ACM

Re: IdentifyTask with multi Polygons as geometry input

ThaoLe — Fri, 11 May 2012 20:15:47 GMT

You can do this by calling multiple IdentifyTasks. Here's one workflow you may follow:

1. Create an IdentifyTask that performs the identify for one geometry
2. After the results are returned, store the results in a global variable
3. Within the same result event, call the second IdentifyTask
4. In the results for the second IdentifyTask, store the results into the same global variable as the first IdentifyTask
5. Repeat this as many times as you want

Once you've completed all the IdentifyTasks, loop through all the results in the global variable. You should now have all the results from all the IdentifyTasks that you ran.

Hope this helps!

Re: IdentifyTask with multi Polygons as geometry input

derekswingley1 — Fri, 11 May 2012 20:23:56 GMT

If you want to use multiple features as the geometry for an identify task, I would send them off to a geometry service's union operation and use the result of that as your identifyParameters.geometry parameter.

Re: IdentifyTask with multi Polygons as geometry input

ThaoLe — Fri, 11 May 2012 20:32:27 GMT

If you want to use multiple features as the geometry for an identify task, I would send them off to a geometry service's union operation and use the result of that as your identifyParameters.geometry parameter.

This is an even better idea!

Re: IdentifyTask with multi Polygons as geometry input

AdrianMarsden — Sat, 12 May 2012 06:33:26 GMT

Thanks for that - after posting I had a quick go at the loop/multiple Id tasks and it did what I wanted without too much hacking of the code. I need to include a bit of logic to exclude duplicate answers - I'll remember the other way for next time.