A feature has a geometry, multiple attributes, and, potentially, attachments. For details about editing and creating geometry, see Edit geometry. If you want to allow users to edit existing attributes and attachments, the recommendation is to use feature forms; see Edit using feature forms. If you are calculating values for attributes and attachments without user input, see the following sections about creating, deleting, and updating a feature using the FeatureTable API.
Create, delete, update features with FeatureTable
You can create or delete features, or update existing features, using the FeatureTable API.
The API gives you more fine-grained control over feature editing operations, including create and edit features, add, edit, or remove feature attachments, and edit feature geometry.
For editing workflows that use a local geodatabase, you can use geodatabase transactions to group and manage a set of edits as a single item (transaction). This makes it easier to control when those edits are committed (saved) or rolled back (discarded) as a single unit.
The enterprise geodatabase can use versioning to support multiuser editing scenarios and long transactions. If you require multiple editors to concurrently access services with the ability to undo and redo their edits, you can implement branch versions in your ArcGIS Enterprise portal. For more information, see Branch versioned data in this guide or Share branch versioned data in the ArcGIS Pro documentation.
For some feature service editing workflows, it's recommended that an analyst using ArcGIS Pro periodically review edits and verify data integrity. Although the API can perform some types of data validation, other validation tasks, such as validating topologies, cannot be performed using the API alone.
If necessary, feature editing can be separated into two parts: geometry editing and attribute editing. In certain scenarios, you may only be interested in editing the location of a feature, while at other times you might only want to edit attributes and attachments. The referenced documentation explores editing the individual parts of the feature in greater detail.
Add features
Apps often allow users to create a new feature by clicking on the map to indicate the feature's location. You can provide this capability by listening for a click event on your map view and adding a new feature in the event handler.
To add features to a feature table, create a new feature from geometry (for example, point, line, or polygon), create attributes for the new feature, and then call add feature. This adds the feature to a table stored locally on your device.
If these local edits need to be shared with the parent feature service, call ServiceGeodatabase.ApplyEditsAsync() on the table's ServiceGeodatabase. See Apply edits from the service geodatabase for more information.
private async Task AddFeature(MapPoint structureLocation, string type, string cause)
{
// Create attributes for the feature.
Dictionary<string, object> attributes = new()
{
{ "typdamage", type },
{ "primcause", cause }
};
// Create a new feature from the attributes and the point.
Feature newFeature = _damagePointsTable.CreateFeature(attributes, structureLocation);
// Add the feature to the local table.
await _damagePointsTable.AddFeatureAsync(newFeature);
// If the feature table is a service feature table then
// apply edits to its service geodatabase.
//var editResults = await _serviceGdb.ApplyEditsAsync();
}
Add true curves
Your app can add features with true curves to ArcGIS feature services that support true curves.
You can use ArcGISFeatureServiceInfo to find out what type of curve support a feature service has and adapt your app's behavior accordingly. For example, if the service doesn't support true curves, you can densify any curve geometries before sending them to the service. Or, if the service does support true curves, you could use the ServiceCurveGeometryMode to fetch curve geometries, and reactively enable a curve-aware user experience in your app. ArcGIS REST API feature service reference contains more details about curve support.
For geometry information about true curves, see the Segments section in the Geometry topic.
Delete features
You can delete several features from a feature table using the delete features method that accepts a list of features, or just a single feature with a call to delete feature. All edits are stored in the feature table on the client.
If these edits need to be shared with the parent feature service, apply them to the table's service geodatabase. See Apply edits from the service geodatabase for more information.
private async Task DeleteSelectedFeatures(FeatureLayer damageLayer)
{
// Get all selected features in the layer.
FeatureQueryResult selectedFeatures = await damageLayer.GetSelectedFeaturesAsync();
// Delete the selected features.
await _damagePointsTable.DeleteFeaturesAsync(selectedFeatures);
// If the feature table is a service feature table then
// apply edits to its service geodatabase.
// var editResults = await _serviceGdb.ApplyEditsAsync();
}
Update features
Feature updates include moving or reshaping a feature's geometry or making edits to attribute values. All edits are stored in the feature table on the client.
If these edits need to be shared with the parent feature service, apply them to the table's service geodatabase. See Apply edits from the service geodatabase for more information.
private async Task UpdateFeature(ArcGISFeature arcgisFeature)
{
// Change the feature's attribute value.
arcgisFeature.Attributes["typdamage"] = "Inaccessible";
// Change the feature's geometry.
MapPoint location = arcgisFeature.Geometry as MapPoint;
MapPoint newLocation = new MapPoint(location.X, location.Y + 50000);
arcgisFeature.Geometry = newLocation;
// Update the feature on the local table.
await _damagePointsTable.UpdateFeatureAsync(arcgisFeature);
// If the feature table is a service feature table then
// apply edits to its service geodatabase.
// var editResults = await _serviceGdb.ApplyEditsAsync();
}
Update true curves
Feature services can be published with protections that disallow edits to existing true curves from curve-unaware clients. If your app supports preserving curve segments when editing, you can use the new ServiceCurveGeometryMode and ServiceCurveGeometryMode enum to inform the service your app is a true-curve client. Use properties on ArcGISFeatureServiceInfo to find out what curve support a feature service has. ArcGIS REST API feature service reference contains more details about curve support.
Edit attachments
If the feature's table has attachments enabled, you can associate documents and photographs with individual features. You can add any file, that has a supported attachment format, to the feature's collection of attachments using ArcGISFeature.AddAttachmentAsync(). For more information about enabling attachments on the feature layer, see the ArcGIS Online, ArcGIS Enterprise, and ArcGIS Pro documentation.
// Check if the table supports attachments.
if (_damagePointsTable.HasAttachments)
{
// Add an attachment (image).
// The content type string is the MIME type for JPEG files.
await _selectedFeature.AddAttachmentAsync
(imageFile.Name,
"image/jpeg",
attachmentData);
}
If the feature's table has attachments enabled and the feature's attachment collection can be edited, you can update any attachment with new details.
// Verify the table supports attachments and the feature's attachments can be edited.
if (_damagePointsTable.HasAttachments &&
_selectedFeature.CanEditAttachments)
{
// Update the attachment with a new image (other properties are retained).
await _selectedFeature.UpdateAttachmentAsync
(selectedAttachment,
selectedAttachment.Name,
selectedAttachment.ContentType,
attachmentData);
}
Or, you can remove any attachment from the feature's attachment collection.
// Delete one of the attachments for the selected feature.
await _selectedFeature.DeleteAttachmentAsync(selectedAttachment);
Undo changes
There are times when making changes to data that you might want to undo all the edits in all of the local tables you are working with. The ServiceGeodatabase, a container for a collection of ServiceFeatureTables connected to a feature service, provides ServiceGeodatabase.HasLocalEdits() to determine if any of the tables have unapplied edits. If you confirm that edits exist, then you can use ServiceGeodatabase.UndoLocalEditsAsync() to asynchronously undo all of the local edits in all the tables. This logic could be applied before or after you apply or synchronize edits back to the feature service. In addition, you could utilize this logic during an editing workflow where you wish to provide a UI component to allow a user to undo their changes.
// Undo all local edits for the version
if(serviceGdb.HasLocalEdits()) {
await serviceGdb.UndoLocalEditsAsync();
}
Work with geometry
There are many ways you can create or edit geometries while editing features. If you have your geometry coordinates prepared before you begin, you can use geometry constructors to create the geometry all at once. When a more iterative process is required, you may need geometry builders to build or edit your geometry. Some actions that you perform on existing geometries can result in new geometries. In this case, the geometry engine provides geometric operations to help with that workflow. Lastly, if your application users want to create or edit geometries interactively in a map view, you can use the geometry editor. To learn more about these options and to help you determine which one fits your requirements, see the Edit geometry topic.
Work with attributes and attachments
The code examples illustrated above show a typical workflow for editing attribute values and attachments when adding, deleting, and updating features. In these scenarios, the manner in which the attribute values are obtained and validated are left to your creativity during application development.
Layers that implement IFeatureFormSource support a ** feature form** that is designed to ease attribute and attachment editing and validation for a feature. This form guides the users to the correct fields, constrains allowed values for a field, and supports the addition of new attachments or replacement of existing ones. We recommend that you display this feature form in your app by utilizing the FeatureFormView toolkit component. For more information, see the Edit using toolkit topic in this guide.
Edit data from a branch version
Edits can be made to service feature tables from a branch version the same way they are made to any ServiceFeatureTable. You can also follow the process described above for adding, deleting, and updating features or their attachments.