Learn how to use a URL to access and
display a feature layer

A map
A feature layerx,y coordinates and a spatial reference.
In this tutorial, you use URLs to access and display three different feature layers
Prerequisites
Before starting this tutorial:
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You need an ArcGIS Location Platform or ArcGIS Online account.
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Ensure your development environment meets the system requirements.
Optionally, you may want to install the ArcGIS Maps SDK for .NET to get access to project templates in Visual Studio (Windows only) and offline copies of the NuGet packages.
Develop or download
You have two options for completing this tutorial:
Option 1: Develop the code
To start the tutorial, complete the Display a map tutorial. This creates a map to display the Santa Monica Mountains in California using the topographic basemap from the ArcGIS Basemap Styles service
Open a Visual Studio solution
- Open the Visual Studio solution you created by completing the Display a map tutorial.
- Continue with the following instructions to add feature layers that will display above the basemap.
Update the tutorial name used in the project (optional)
The Visual Studio solution, project, and the namespace for all classes currently use the name DisplayAMap. You can rename these if you prefer them to reflect the current tutorial. Renaming is not required, your code will still work if you keep the original name.
The tutorial instructions and code use the name AddAFeatureLayer for the solution, project, and namespace. You can choose any name you like, but it should be the same for each of these.
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Update the name for the solution and the project.
- In Visual Studio, in the Solution Explorer, right-click the solution name and choose Rename. Provide the new name for your solution.
- In the Solution Explorer, right-click the project name and choose Rename. Provide the new name for your project.
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Rename the namespace used by classes in the project.
- In the Solution Explorer, expand the project node.
- Double-click MapViewModel.cs in the Solution Explorer to open the file.
- In the
MapViewModelclass, double-click the namespace name (DisplayAMap) to select it, and then right-click and choose Rename…. - Provide the new name for the namespace.
- Click Apply in the Rename: DisplayAMap window that appears in the upper-right of the code window. This will rename the namespace throughout your project.
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Build the project.
- Choose Build > Build solution (or press <F6>).
Create URIs to reference feature service data
To display three new data layersFeatureLayers using URIs to reference datasets hosted in ArcGIS Online
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Open a browser and navigate to the URL for Parks and Open Spaces to view metadata about the layer. To display the layer in your app, you only need the URL.
The ArcGIS REST Services Directory page provides information such as the geometry
A geometry is a geometric shape, such as a point, polyline, or polygon, that contains one or more coordinates and a spatial reference. type, the geographic extentAn extent is a bounding rectangle with points that delineate an area for a map or scene. , the minimum and maximum scaleZoom level is a value that sets the scale for a map view or a scene view. at which features are visible, and the attributesAttributes are fields and values for a single feature or non-spatial record. They are typically stored in a database or service such as a feature service. (fields) it contains. You can preview the layer by clicking on ArcGIS.com Map in the “View In:” list at the top of the page. -
In the Visual Studio > Solution Explorer, double-click MapViewModel.cs to open the file.
The project uses the Model-View-ViewModel (MVVM) design pattern to separate the application logic (view model) from the user interface (view).
MapViewModel.cscontains the view model class for the application, calledMapViewModel. See the Microsoft documentation for more information about the Model-View-ViewModel pattern. -
In the
SetupMap()function, add code that defines the URIs to the hosted layers. You will add: Trailheads (points), Trails (lines), and Parks and Open Spaces (polygons).46 collapsed lines// Copyright 2021 Esri// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at//// https://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License.using System;using System.Collections.Generic;using System.Text;using Esri.ArcGISRuntime.Geometry;using Esri.ArcGISRuntime.Mapping;using System.ComponentModel;using System.Runtime.CompilerServices;namespace AddAFeatureLayer{class MapViewModel : INotifyPropertyChanged{public MapViewModel(){SetupMap();}public event PropertyChangedEventHandler? PropertyChanged;protected void OnPropertyChanged([CallerMemberName] string propertyName = ""){PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));}private Map? _map;public Map? Map{get { return _map; }set{_map = value;OnPropertyChanged();}}private void SetupMap(){// Create a new map with a 'topographic vector' basemap.Map map = new Map(BasemapStyle.ArcGISTopographic);// Set the initial viewpoint around the Santa Monica Mountains in California.var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);// Set the view model's Map property with the map.Map = map;var parksUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/ArcGIS/rest/services/Parks_and_Open_Space/FeatureServer/0");var trailsUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/ArcGIS/rest/services/Trails/FeatureServer/0");var trailheadsUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0");4 collapsed lines}}}
Create feature layers to display the hosted data
You will create three new FeatureLayer to display the hosted layer at each URI.
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In the
SetupMap()function, create new feature layers and pass the appropriate URI to the constructor for each.66 collapsed lines// Copyright 2021 Esri// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at//// https://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License.using System;using System.Collections.Generic;using System.Text;using Esri.ArcGISRuntime.Geometry;using Esri.ArcGISRuntime.Mapping;using System.ComponentModel;using System.Runtime.CompilerServices;namespace AddAFeatureLayer{class MapViewModel : INotifyPropertyChanged{public MapViewModel(){SetupMap();}public event PropertyChangedEventHandler? PropertyChanged;protected void OnPropertyChanged([CallerMemberName] string propertyName = ""){PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));}private Map? _map;public Map? Map{get { return _map; }set{_map = value;OnPropertyChanged();}}private void SetupMap(){// Create a new map with a 'topographic vector' basemap.Map map = new Map(BasemapStyle.ArcGISTopographic);// Set the initial viewpoint around the Santa Monica Mountains in California.var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);// Set the view model's Map property with the map.Map = map;var parksUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/ArcGIS/rest/services/Parks_and_Open_Space/FeatureServer/0");var trailsUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/ArcGIS/rest/services/Trails/FeatureServer/0");var trailheadsUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0");var parksLayer = new FeatureLayer(parksUri);var trailsLayer = new FeatureLayer(trailsUri);var trailheadsLayer = new FeatureLayer(trailheadsUri);4 collapsed lines}}} -
Add the feature layers to the map. Data layers
A data layer is a layer that references geographic data from a file or a service and is used to visualize the data in a map or scene. are displayed in the order in which they are added. PolygonA polygon is a type of geometry containing an array of rings and a spatial reference. Each ring contains an array of point coordinates, where the first and last point are the same. layers should be added before layers with linesA polyline is a type of geometry containing ordered point coordinates and a spatial reference. or pointsA point is a type of geometry containing a single set of if there’s a chance the polygon symbols will obscure features beneath.x,ycoordinates and a spatial reference.70 collapsed lines// Copyright 2021 Esri// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at//// https://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License.using System;using System.Collections.Generic;using System.Text;using Esri.ArcGISRuntime.Geometry;using Esri.ArcGISRuntime.Mapping;using System.ComponentModel;using System.Runtime.CompilerServices;namespace AddAFeatureLayer{class MapViewModel : INotifyPropertyChanged{public MapViewModel(){SetupMap();}public event PropertyChangedEventHandler? PropertyChanged;protected void OnPropertyChanged([CallerMemberName] string propertyName = ""){PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));}private Map? _map;public Map? Map{get { return _map; }set{_map = value;OnPropertyChanged();}}private void SetupMap(){// Create a new map with a 'topographic vector' basemap.Map map = new Map(BasemapStyle.ArcGISTopographic);// Set the initial viewpoint around the Santa Monica Mountains in California.var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);// Set the view model's Map property with the map.Map = map;var parksUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/ArcGIS/rest/services/Parks_and_Open_Space/FeatureServer/0");var trailsUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/ArcGIS/rest/services/Trails/FeatureServer/0");var trailheadsUri = new Uri("https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0");var parksLayer = new FeatureLayer(parksUri);var trailsLayer = new FeatureLayer(trailsUri);var trailheadsLayer = new FeatureLayer(trailheadsUri);map.OperationalLayers.Add(parksLayer);map.OperationalLayers.Add(trailsLayer);map.OperationalLayers.Add(trailheadsLayer);4 collapsed lines}}} -
Click Debug > Start Debugging (or press <F5> on the keyboard) to run the app. If your app uses user authentication, enter your ArcGIS Online credentials when prompted.
You should see point, line, and polygon features (representing trailheads, trails, and parks) draw on the map for an area in the Santa Monica Mountains.
Alternatively, you can download the tutorial solution, as follows.
Option 2: Download the solution
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Click the Download solution link in the right-hand panel of the page.
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Unzip the file to a location on your machine.
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Open the
.slnfile in Visual Studio.
Since the downloaded solution does not contain authentication credentials, you must first set up authentication to create credentials, and then add the developer credentials to the solution.
Set up authentication
To access the secure ArcGIS location services
You can implement API key authentication or user authentication in this tutorial. Compare the differences below:
API key authentication
- Users are not required to sign in.
- Requires creating an API key credential
API key credentials are an item that contains the parameters used to create and manage long-lived access tokens for API key authentication. They are a type of developer credential. with the correct privileges. - API keys
An API key is a long-lived access token created using API key credentials. They are valid for up to one year and are typically embedded directly into client applications. are long-lived access tokens. - Service usage is billed to the API key owner/developer.
- Simplest authentication method to implement.
- Recommended approach for new ArcGIS developers.
Learn more in API key authentication.
User authentication
- Users are required to sign in with an ArcGIS account
An ArcGIS account is an identity with a user type and set of privileges that can access specific ArcGIS products, tools, APIs, services, and resources. The main account types that can be used for development are an ArcGIS Location Platform account, ArcGIS Online account, and ArcGIS Enterprise account. ArcGIS Location Platform and ArcGIS Online accounts are also associated with a subscription. . - User accounts must have privilege
Privileges are a set of permissions assigned to ArcGIS accounts, developer credentials, and applications that grant access to secure resources and functionality in ArcGIS. to access the ArcGIS servicesA service, also known as an ArcGIS service, is software that supports an ArcGIS REST API and provides geospatial functionality or data. A service can be hosted by Esri or in ArcGIS Enterprise. used in application. - Requires creating OAuth credentials
OAuth credentials are an item that contains parameters required to implement user authentication or app authentication, including a .client_id,client_secret, and redirect URIs. They are a type of developer credential. - Application uses a redirect URL and client ID.
- Service usage is billed to the organization of the user signed into the application.
Learn more in User authentication.
To complete this tutorial, click on the tab in the switcher below for your authentication type of choice, either API key authentication or User authentication.
Create a new API key access token
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Complete the Create an API key tutorial and create an API key with the following privilege(s)
Privileges are a set of permissions assigned to ArcGIS accounts, developer credentials, and applications that grant access to secure resources and functionality in ArcGIS. :- Privileges
- Location services > Basemaps
- Privileges
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Copy and paste the API key access token into a safe location. It will be used in a later step.
Create new OAuth credentials to access the secure resources used in this tutorial.
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Complete the Create OAuth credentials for user authentication tutorial to obtain a Client ID and Redirect URL.
A
Client IDuniquely identifies your app on the authenticating server. If the server cannot find an app with the provided Client ID, it will not proceed with authentication.The
Redirect URL(also referred to as a callback url) is used to identify a response from the authenticating server when the system returns control back to your app after an OAuth login. Since it does not necessarily represent a valid endpoint that a user could navigate to, the redirect URL can use a custom scheme, such asmy-app://auth. It is important to make sure the redirect URL used in your app’s code matches a redirect URL configured on the authenticating server. -
Copy and paste the Client ID and Redirect URL into a safe location. They will be used in a later step.
All users that access this application need account privileges
Set developer credentials in the solution
To allow your app users to access ArcGIS location services
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In Visual Studio, in the Solution Explorer, click App.xaml.cs to open the file.
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Set the
ArcGISEnvironment.ApiKeyproperty with your API key access token.App.xaml.csprotected override void OnStartup(StartupEventArgs e){base.OnStartup(e);// Set the access token for ArcGIS Maps SDK for .NET.Esri.ArcGISRuntime.ArcGISRuntimeEnvironment.ApiKey = "YOUR_ACCESS_TOKEN";// Call a function to set up the AuthenticationManager for OAuth.UserAuth.ArcGISLoginPrompt.RegisterOAuthConfig();} -
Remove the code that sets up user authentication.
App.xaml.csprotected override void OnStartup(StartupEventArgs e){base.OnStartup(e);// Set the access token for ArcGIS Maps SDK for .NET.Esri.ArcGISRuntime.ArcGISRuntimeEnvironment.ApiKey = "YOUR_ACCESS_TOKEN";// Call a function to set up the AuthenticationManager for OAuth.UserAuth.ArcGISLoginPrompt.RegisterOAuthConfig();}
Best Practice: The access token is stored directly in the code as a convenience for this tutorial. Do not store credentials directly in source code in a production environment.
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From the Visual Studio Solution explorer window, open the
ArcGISLoginPrompt.csfile. -
Set your values for the client ID (
OAuthClientID) and the redirect URL (OAuthRedirectUrl). These are the user authentication settings you created in the Set up authentication step.ArcGISLoginPrompt.csinternal static class ArcGISLoginPrompt{private const string ArcGISOnlineUrl = "https://www.arcgis.com/sharing/rest";// Specify the Client ID and Redirect URL to use with OAuth authentication.// See the instructions here for creating OAuth app settings:// https://developers.arcgis.com/documentation/security-and-authentication/user-authentication/tutorials/create-oauth-credentials-user-auth/private const string AppClientId = "YOUR_CLIENT_ID";private const string OAuthRedirectUrl = "YOUR_REDIRECT_URL"; -
In Visual Studio, in the Solution Explorer, click App.xaml.cs to open the file.
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Remove the line of code that sets an API key access token.
App.xaml.csprotected override void OnStartup(StartupEventArgs e){base.OnStartup(e);// Set the access token for ArcGIS Maps SDK for .NET.Esri.ArcGISRuntime.ArcGISRuntimeEnvironment.ApiKey = "YOUR_ACCESS_TOKEN";// Call a function to set up the AuthenticationManager for OAuth.UserAuth.ArcGISLoginPrompt.RegisterOAuthConfig();}
Best Practice: The OAuth credentials are stored directly in the code as a convenience for this tutorial. Do not store credentials directly in source code in a production environment.
Run the solution
Click Debug > Start Debugging (or press <F5> on the keyboard) to run the app. If your app uses user authentication, enter your ArcGIS Online credentials when prompted.
You should see point, line, and polygon features (representing trailheads, trails, and parks) draw on the map for an area in the Santa Monica Mountains.
What’s next?
Learn how to use additional API features, ArcGIS location services, and ArcGIS tools in these tutorials: