Editing

When to use: Activate this skill whenever the user creates/updates/deletes features, builds an editing UI, or manages attachments.

Overview

Editing persists feature changes to a service. Use the editor component for UI, or applyEdits in code.

• Problem it solves: create/update/delete (CRUD) on editable feature services.
• Who it serves: developers building data-collection and maintenance apps.
• Pattern it teaches: arcgis-editor for turnkey UI; applyEdits for programmatic control.
• What it does NOT cover: drawing geometry (see arcgis-interaction) or forms (see arcgis-tables-forms).

Quick Start

const result = await layer.applyEdits({ addFeatures: [graphic] });
console.log(result.addFeatureResults[0].objectId);

Decision Tree

1. Want a ready-made editing UI?
   • Yes → arcgis-editor component.
2. Need programmatic control / custom UI?
   • Yes → layer.applyEdits({ addFeatures, updateFeatures, deleteFeatures }).
3. Editing files/photos on features?
   • Yes → layer.addAttachment / queryAttachments.

Default: arcgis-editor for standard workflows; applyEdits for custom logic.

Import Patterns

Direct ESM (recommended for npm/Vite/Webpack)

import FeatureLayer from "@arcgis/core/layers/FeatureLayer.js";

Dynamic Imports (CDN)

const FeatureLayer = await $arcgis.import("@arcgis/core/layers/FeatureLayer.js");

Map Components (recommended for new projects)

import "@arcgis/map-components/components/arcgis-editor";

Key Concepts

Concept 1: applyEdits

layer.applyEdits({ addFeatures, updateFeatures, deleteFeatures }) resolves to result arrays; each item has objectId and error. Measured with 5.1.27 on a client-side layer:

• A bad edit does not reject the promise: it comes back as error in its result ("Identifier fields: OBJECTID missing", "Feature with object id 9999 missing").
• It is not transactional: in a batch with one valid and one invalid update, the valid one is applied. For a service, applyEdits(edits, { rollbackOnFailureEnabled: true }) asks for all-or-nothing (not measured here).
• Silent successes: deleting an objectId that does not exist returns ok; an attribute whose name is not a field (ESTADO) is dropped and the update still returns ok. Field names are matched case-insensitively (status updated STATUS).
• The whole call rejects only for layer-level problems: editingEnabled: false ("Editing is disabled for layer") or z-values on a layer without z.
• Geometry in another spatial reference is projected for you (a 3857 point was stored in 4326 at -74.0806, 4.6000), and the layer view updates without refresh() (2 → 3 features; one edits event).

Concept 2: The editor component

arcgis-editor replaces the Editor widget (deprecated since 5.0). Bind it with reference-element; with layerInfos unset it edits every editable layer of the map (measured: state === "ready"). It also has startUpdateFeaturesWorkflow, merge and split workflows, and in 5.1 the snapping grid controls (hide-snapping-controls-elements-grid-*).

Concept 3: Attachments

When layer.capabilities.data.supportsAttachment is true, use addAttachment(feature, form) (a FormData or <form>) and queryAttachments({ objectIds }), which resolves to { [objectId]: AttachmentInfo[] }.

Common Pitfalls (Top 3)

Pitfall 1: Ignoring per-edit errors

// ❌ Anti-pattern
await layer.applyEdits({ updateFeatures }); // assume success

// ✅ Correct
const r = await layer.applyEdits({ updateFeatures });
r.updateFeatureResults.forEach((res) => { if (res.error) console.error(res.error); });

Impact: measured: an update with a missing id resolves normally; only its result carries the error. A try/catch around applyEdits does not see it.

Pitfall 2: Editing a non-editable layer

// ❌ Anti-pattern
await layer.applyEdits({ addFeatures }); // service has no create capability

// ✅ Correct
await layer.load();
if (layer.editingEnabled && layer.capabilities?.operations?.supportsAdd) await layer.applyEdits({ addFeatures });

Impact: measured on a MapServer layer: supportsAdd, supportsUpdate, supportsEditing and editingEnabled are all false. With editingEnabled: false the call rejects with "Editing is disabled for layer".

Pitfall 3: Updating without the objectId

// ❌ Anti-pattern
const g = new Graphic({ attributes: { STATUS: "done" } }); // no OBJECTID
await layer.applyEdits({ updateFeatures: [g] });

// ✅ Correct
const g = new Graphic({ attributes: { [layer.objectIdField]: 42, STATUS: "done" } });
await layer.applyEdits({ updateFeatures: [g] });

Impact: measured: no exception; the result says "Identifier fields: OBJECTID missing" and no row changes. Use layer.objectIdField: it is not always OBJECTID (FID, objectid).

When to Read references/

Related Skills

• arcgis-tables-forms — attribute forms for editing
• arcgis-interaction — draw geometries to edit
• arcgis-layers — the editable FeatureLayer

Reference Samples

• applyEdits
• Editor component

Changelog

• 0.2.0 (2026-10-27): SDK 5.1. The code ran; two extended pitfalls were false: geometry in another spatial reference is projected for you (not misplaced or rejected) and the layer view updates without refresh(). Replaced by what does fail silently: deleting a missing id returns ok, unknown fields are dropped with ok. Measured that bad edits never reject the promise, that batches are not transactional, and which errors do reject. objectIdField instead of a hard-coded OBJECTID. Run in tests/runtime/casos/arcgis-editing.ts.
• 0.1.0 (2026-05-31): Initial release.