topic Re: Within() Arcade Function and multi-layer feature services in ArcGIS Online Questions

Within() Arcade Function and multi-layer feature services

AmyRoust — Mon, 06 Oct 2025 17:33:21 GMT

Is there a trick to using the Within function when referencing a layer in a multi-layer feature layer? I used a simple Within function to add the intersecting parcel PIN number to an address point's pop-up, but when I try to get its zoning, here's what happens:

If I comment out the Within function and just tell it to return all zoning data, it works:

The difference between my parcel feature layer and my zoning feature layer is that the zoning layer has three layers in it:

The FeatureSetByName function doesn't seem to care that it's in a group, but maybe Within does?

I did try adding the Lawrence Zoning District sublayer by itself to the map, but I got the same results.

Re: Within() Arcade Function and multi-layer feature services

RPGIS — Mon, 06 Oct 2025 20:11:20 GMT

Hi @AmyRoust,

So the within function returns a feature set of the features that fall within the specified layer. If you have an instance where some layers may overlap others then what I might suggest is any of the following.

var FS = FeatureSetByName($map, 'Zoning Districts - Lawrence Zoning District',['ZoningDistrict'],True) var Address = $feature if( TypeOf(Geometry($feature)) == 'Polygon' ){ Address = Centroid($feature) } var AddrWithin = Within(address,FS) iif( Count(AddrWithin)>0, AddrWithin, 'No features are within the layer') /* Note: the intersects function can also be used if the input layer is a point feature. */

Re: Within() Arcade Function and multi-layer feature services

AmyRoust — Mon, 06 Oct 2025 20:50:44 GMT

@RPGIS - no luck, but I appreciate the suggestion.

Re: Within() Arcade Function and multi-layer feature services

RPGIS — Mon, 06 Oct 2025 22:08:14 GMT

Then it might helpful then to use the intersects function to get the information that you need. It may also require that you loop through multiple features to get a dictionary of field values to pull from.

Re: Within() Arcade Function and multi-layer feature services

KenBuja — Mon, 06 Oct 2025 23:19:41 GMT

It doesn't matter if you have the layer within a group layer. This works on a test I set up.

var fs = FeatureSetByName($map, "USA Census States") var output = Within($feature,FS) return { type : 'text', text : first(output).STATE_NAME }

Did you test the code on an actual feature in the Zoning District? Running the code in the editor will use the first feature in the FeatureSet, which may or may not give you a feature within the Zoning District layer. You can use a feature you know will work by filtering the parcel to a specific one. In my example, I can filter the earthquakes to a specific event to test it out.

This code

var feat = First(Filter($layer, "id = 'mb90114598'")) var fs = FeatureSetByName($map, "USA Census States") var output = Within(feat,FS) return output return { type : 'text', text : first(output).STATE_NAME }

returns this

The code in your latest post fails because you're supplying an incorrect name for the FeatureSetByName function, which returns a null. When used in the WIthin function, it's being interpreted as a null feature in the Geometry Within function (which returns a boolean) instead of the FeatureSet Within function (which returns a FeatureSet)

Re: Within() Arcade Function and multi-layer feature services

RPGIS — Tue, 07 Oct 2025 13:18:14 GMT

Hi @KenBuja,

Correct me if I am wrong but it might appear that @AmyRoust is referencing a grouped layer which, if it is setup correctly, should be a single service in which case the Within function should work. However, if it is created as separate feature services which are then grouped in the map then that would require a different work around. In which case @AmyRoust could try one of the following below.

// Option 1: using union then the within function var FSets = [ FeatureSetByName($map,'ConditionalZoning'),['*'],True), FeatureSetByName($map,'LawrenceZoningDistrict'),['*'],True), FeatureSetByName($map,'DouglasCountyZoningDistrict'),['*'],True) ] var UnionSets = Union(FSets) var Address = $feature var Check = Within(Address,UnionSets) iif( TypeOf( Check ) == 'FeatureSet', Check, 'Nothing Within') // Option 2: looping through a list of layers and getting the appropriate values var FSets = [ FeatureSetByName($map,'ConditionalZoning'),['*'],True), FeatureSetByName($map,'LawrenceZoningDistrict'),['*'],True), FeatureSetByName($map,'DouglasCountyZoningDistrict'),['*'],True) ] var Address = $feature var TextValues = [] for( var fs in FSets ){ fs = FSets[i] var V = First(Intersects(Address,fs)) if(TypeOf(intfs)=='Feature'){ Push(TextValues,V['<fieldname>']) } } iif( Count(TextValues)>0, Concatenate(TextValues,'\n'), 'Address does not fall within')

Re: Within() Arcade Function and multi-layer feature services

AmyRoust — Tue, 07 Oct 2025 20:15:09 GMT

@RPGIS your first assumption is correct - all three layers are published as one service. I only need to pull the intersecting value from the Lawrence Zoning District layer, but it wouldn't hurt to pull the value from the Conditional Zoning layer. Either way, neither Within() nor Intersects() works with the zoning service. It does work with our parcel service.

The parcel service just has one layer, which is what led me to suspect that the multi-layer service was the issue for me. I took that exact block of code in the screenshot above and just swapped out parcel for zoning, and it returns an error.

@KenBuja you asked, "Did you test the code on an actual feature in the Zoning District?" Yes, I did try that. No luck.

All three of these services are public, so if anyone wants to test on the actual data, here are links to the item pages in AGO:

Address Point: https://lawrenceks.maps.arcgis.com/home/item.html?id=0e4a33c0f05e483284f046c220b8f0c0

Parcel: https://lawrenceks.maps.arcgis.com/home/item.html?id=08285f4b4aca41a785afcc47c5044d2e

Zoning Districts: https://lawrenceks.maps.arcgis.com/home/item.html?id=8cfd05010c2d4cc499cc701c91e3c2b0

Re: Within() Arcade Function and multi-layer feature services

KenBuja — Tue, 07 Oct 2025 20:58:27 GMT

I've used your layers in a map and it works as expected. The code I'm using is

var fs = FeatureSetByName($map, "Lawrence Zoning District", ["ZoningDistrict"]); var WithinFS = Within($feature, fs); iif( Count(WithinFS) == 0, "Not in a zoning district.", First(WithinFS).ZoningDistrict );

which returns this when run in the text editor (using iif to return a message if there are no features returned by the Within)

and this in the popup ("R-2", circled in red)

Re: Within() Arcade Function and multi-layer feature services

RPGIS — Tue, 07 Oct 2025 21:20:17 GMT

Hi @AmyRoust . Try the following.

var P = Portal('https://lawrenceks.maps.arcgis.com/') var Addr = FeatureSetByPortalItem(P, '0e4a33c0f05e483284f046c220b8f0c0',0,['*'],True) var Parcs = FeatureSetByPortalItem(P, '8cfd05010c2d4cc499cc701c91e3c2b0','*',['*'],True) var Test = [] for( var i in Parcs){ var N = First(Intersects( Addr, Geometry(i))) if( TypeOf(N)=='Feature' ){ N = Dictionary(N).attributes Console(N) Push(Test,N) } if( Count(Test) <= 10 ){Break} } If( Count(Test)>0){ Console(Concatenate(Test,'\n')) }

You can play around with it in the Arcade Playground.

Re: Within() Arcade Function and multi-layer feature services

AmyRoust — Wed, 08 Oct 2025 13:17:01 GMT

@KenBuja - that worked! Looks like adding First() is what I needed. Seems odd to me that it didn't need that function for the parcel layer, but perhaps there is some overlapping geometry in the zoning that I need to find.

Thank you and @RPGIS for sticking with me on this.