IdentifyFeatures

Identify features at a point across multiple layers in an ArcGIS MapServer.

Interactive Demo

Click anywhere on the map to identify features. Use the layer checkboxes to control which layers are queryable.

Quick Start

import { IdentifyFeatures } from 'esri-gl';

const identifyTask = new IdentifyFeatures({
  url: 'https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer',
});

const results = await identifyTask
  .at({ lng: -100, lat: 40 }, map)
  .layers([0, 1, 2])
  .tolerance(5)
  .returnGeometry(true);

Constructor

new IdentifyFeatures(options: IdentifyOptions)

Options

Option	Type	Default	Description
url	string		Required. MapServer URL
layers	Array<number> | string	'all'	Layers to identify
tolerance	number	3	Search tolerance in pixels
returnGeometry	boolean	false	Include feature geometry
maxAllowableOffset	number		Geometry simplification
geometryPrecision	number		Decimal places for geometry
dynamicLayers	Array<object>		Dynamic layer definitions
mapExtent	object		Current map extent
imageDisplay	object		Map image parameters
returnFieldName	boolean	false	Return field names with values
returnUnformattedValues	boolean	false	Return raw field values
token	string		Authentication token

Chainable Methods

Method	Parameter	Description
.layers(layers)	number[] | string	Set layers to identify (IDs or 'all', 'visible')
.tolerance(pixels)	number	Set search radius in pixels
.returnGeometry(include)	boolean	Include feature geometry in results
.returnFieldName(include)	boolean	Return field names with values
.token(authToken)	string	Set authentication token

Execution Methods

.at(point, map, callback?)

Execute identification at a geographic point. Returns a Promise with results.

• point: {lng: number, lat: number} or [lng, lat]
• map: MapLibre GL or Mapbox GL map instance
• callback: Optional callback function

.on(map)

Bind identify to map click events.

• map: MapLibre GL or Mapbox GL map instance

.run()

Execute the configured identify request manually.

Examples

Basic Identification

const identifyTask = new IdentifyFeatures({
  url: 'https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer',
});

map.on('click', async e => {
  const results = await identifyTask.at(e.lngLat, map);
  console.log('Identified features:', results);
});

With Layer Filtering

const identifyTask = new IdentifyFeatures({
  url: 'https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer',
})
  .layers([0, 1, 2])
  .tolerance(10)
  .returnGeometry(true);

const results = await identifyTask.at({ lng: -95, lat: 37 }, map);