Display a map

Learn how to create and display a map with a basemap layer.

A map contains layers of geographic data. A map contains a basemap layer and, optionally, one or more data layers. You can display a specific area of a map by using a map view and setting the location and zoom level.

In this tutorial, you create and display a map of the Santa Monica Mountains in California using the topographic basemap layer.

The map and code will be used as the starting point for other 2D tutorials.

Prerequisites

Before starting this tutorial:

You need an ArcGIS Location Platform or ArcGIS Online account.
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.

Set up authentication

To access the secure ArcGIS location services used in this tutorial, you must implement API key authentication or user authentication using an ArcGIS Location Platform or an ArcGIS Online account.

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 with the correct privileges.
API keys 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.
User accounts must have privilege to access the ArcGIS services used in application.
Requires creating OAuth credentials.
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.

Create a new API key access token with privileges to access the secure resources used in this tutorial.

Complete the Create an API key tutorial and create an API key with the following privilege(s):
- Privileges
  - Location services > Basemaps
Copy and paste the API key access token into a safe location. It will be used in a later step.

Create a new OAuth credential to access the secure resources used in this tutorial.

Complete the Create OAuth credentials for user authentication tutorial.
Copy and paste the ClientID and RedirectURL into a safe location. They will be used in a later step.

All users that access this application need account privileges to access the basemap styles service.

Develop or download

You have two options for completing this tutorial:

Option 1: Develop the code or
Option 2: Download the completed solution

Option 1: Develop the code

Create a new Visual Studio Project

ArcGIS Maps SDK for .NET supports apps for Windows Presentation Framework (WPF), Universal Windows Platform (UWP), Windows UI Library (WinUI), and .NET MAUI. The instructions for this tutorial are specific to creating a WPF .NET project using Visual Studio for Windows.

Start Visual Studio and create a new project.
- In the Visual Studio start screen, click Create a new project.
- Choose the WPF Application template for C#. If you don't see the template listed, you can find it by typing WPF Application into the Search for templates text box.
- Click Next.
- Provide required values in the Configure your new project panel:
  - Project name: DisplayAMap
  - Location: choose a folder
- Click Next.
  - Choose the framework: .NET 8.0 (Long Term Support)
- Click Create to create the project.

If you are developing with Visual Studio for Windows, ArcGIS Maps SDK for .NET provides a set of project templates for each supported .NET platform. These templates follow the Model-View-ViewModel (MVVM) design pattern. Install the ArcGIS Maps SDK for .NET Visual Studio Extension to add the templates to Visual Studio (Windows only). See Install and set up for details.

Add a reference to the API

Add a reference to the API by installing a NuGet package.
- In Solution Explorer, right-click Dependencies and choose Manage NuGet Packages.
- In the NuGet Package Manager window, ensure the selected Package source is nuget.org (upper-right).
- Select the Browse tab and search for ArcGIS Maps SDK.
- In the search results, select the appropriate package for your platform. For this tutorial project, choose the Esri.ArcGISRuntime.WPF NuGet package.
- Confirm the Latest stable version of the package is selected in the Version dropdown.
- Click Apply.
- The Preview Changes dialog confirms any package(s) dependencies or conflicts. Review the changes and click OK to continue installing the packages.
- Review the license information on the License Acceptance dialog and click I Accept to add the package(s) to your project.
- In the Visual Studio Output window, ensure the packages were successfully installed. If you see an error about the target Windows version, you will fix that in the next step.
- Close the NuGet Package Manager window.
You may see an error like this in the Visual Studio Error List: The 'Esri.ArcGISRuntime.WPF' nuget package cannot be used to target 'net8.0-windows'. Target 'net8.0-windows10.0.19041.0' or later instead.. If so, follow these steps to address it.
- In Solution Explorer, right-click the project entry in the tree view and choose Edit Project File.
- Update the <TargetFramework> element with net8.0-windows10.0.19041.0 (or higher).
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```
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<PropertyGroup>
  <OutputType>WinExe</OutputType>
  <TargetFramework>net8.0-windows10.0.19041.0</TargetFramework>
  <UseWPF>true</UseWPF>
</PropertyGroup>
```
- Save the project file and close it.

Create a view model to store app logic

This app is the foundation for many following tutorials so it's good to build it with a solid design.

The Model-View-ViewModel (MVVM) design pattern provides an architecture that separates user interface elements, and related code, from the underlying app logic. In this pattern,model represents the data consumed in an app, view represents the user interface, and view model contains the logic that binds model and view together. The framework required for such a pattern might initially seem like a lot of work for a small project, but as your project's complexity increases, a solid design foundation will make your code more flexible and easier to maintain.

In an ArcGIS app designed with MVVM, the map view or scene view usually provides the main view component. Many of the classes fill the role of model (representing data as maps, scenes, layers, graphics, features, and others). Much of the code you write will be for the view model component, where you will add logic to work with ArcGIS objects and provide data for display in the view.

Add a new class that will define a view model for the project.
- Click Project > Add Class ....
- Name the new class MapViewModel.cs.
- Click Add to create the new class and add it to the project.
- The new class will open in Visual Studio.

Add required using statements to the view model.

MapViewModel.cs
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using Esri.ArcGISRuntime.Mapping;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using Esri.ArcGISRuntime.Geometry;

Implement the INotifyPropertyChanged interface in the MapViewModel class.

This interface defines a PropertyChanged event that is used to notify clients (views) that a property of the view model has changed.

MapViewModel.cs
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namespace DisplayAMap
{

    internal class MapViewModel : INotifyPropertyChanged
    {

Inside the MapViewModel class, add code to implement the PropertyChanged event.

When a property of the view model changes, a call to OnPropertyChanged will raise this event.

MapViewModel.cs
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    internal class MapViewModel : INotifyPropertyChanged
    {

        public event PropertyChangedEventHandler? PropertyChanged;
        protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }

    }
Expand

Define a new property on the view model called Map that exposes a Map object. When the property is set, call OnPropertyChanged.

MapViewModel.cs
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    internal class MapViewModel : INotifyPropertyChanged
    {

        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();
            }
        }

    }
Expand

Add a function to the MapViewModel class called SetupMap. This function will create a new map and use it to set the Map property.

The map will use one of the secured ArcGIS basemap styles and center on the Santa Monica Mountains in California.

MapViewModel.cs
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        private void SetupMap()
        {

            // Create a new map with a 'topographic vector' basemap.
            var 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;

        }
Expand

Add a constructor to the class that calls SetupMap when a new MapViewModel is instantiated.

When you write code like MapViewModel newMapVM = new MapViewModel();, the class constructor runs. This is a good place to add code that needs to run when the class is initialized.

MapViewModel.cs
Expand
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namespace DisplayAMap
{

    internal class MapViewModel : INotifyPropertyChanged
    {

        public MapViewModel()
        {
            SetupMap();
        }
Expand

Your MapViewModel is complete!

An advantage of using the MVVM design pattern is the ability to reuse code in a view model. Because this API has a nearly-standard API surface across platforms, a view model written for one app typically works on all supported .NET platforms. This view model could be used in a .NET MAUI app, a WinUI app, or a UWP app with little or no modification.

Set developer credentials

To allow your app users to access ArcGIS Location Services, use the developer credentials that you created in the Set up authentication step to authenticate requests for resources.

In the Solution Explorer, expand the node for App.xaml, and double-click App.xaml.cs to open it.

In the App class, add an override for the OnStartup() function to set the ApiKey property on ArcGISRuntimeEnvironment.

App.xaml.cs
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    public partial class App : Application
    {

        protected 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";

        }

    }
}

Replace "YOUR_ACCESS_TOKEN" with the API key access token you created earlier.
Save and close the App.xaml.cs file.

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.

From the Visual Studio Project menu, choose Add class .... Name the class ArcGISLoginPrompt.cs then click Add. The new class is added to your project and opens in Visual Studio.
Select all the code in the new class and delete it.

Copy all of the code below and paste it into the ArcGISLoginPrompt.cs class in your project.

ArcGISLoginPrompt.cs
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// 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: http://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 Esri.ArcGISRuntime.Security;
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using System.Windows.Threading;

namespace UserAuth
{

    internal 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";

        public static async Task<bool> EnsureAGOLCredentialAsync()
        {
            bool loggedIn = false;

            try
            {
                // Create a challenge request for portal credentials (OAuth credential request for arcgis.com)
                CredentialRequestInfo challengeRequest = new CredentialRequestInfo
                {
                    // Use the OAuth authorization code workflow.
                    GenerateTokenOptions = new GenerateTokenOptions
                    {
                        TokenAuthenticationType = TokenAuthenticationType.OAuthAuthorizationCode
                    },

                    // Indicate the url (portal) to authenticate with (ArcGIS Online)
                    ServiceUri = new Uri(ArcGISOnlineUrl)
                };

                // Call GetCredentialAsync on the AuthenticationManager to invoke the challenge handler
                Credential? cred = await AuthenticationManager.Current.GetCredentialAsync(challengeRequest, false);
                loggedIn = cred != null;
            }
            catch (OperationCanceledException)
            {
                // OAuth login was canceled, no need to display error to user.
            }
            catch (Exception ex)
            {
                // Login failure
                MessageBox.Show("Login failed: " + ex.Message);
            }

            return loggedIn;
        }

        public static void SetChallengeHandler()
        {
            var userConfig = new OAuthUserConfiguration(new Uri(ArcGISOnlineUrl), AppClientId, new Uri(OAuthRedirectUrl));
            AuthenticationManager.Current.OAuthUserConfigurations.Add(userConfig);
            AuthenticationManager.Current.OAuthAuthorizeHandler = new OAuthAuthorize();
        }

        #region OAuth handler

        // In a desktop (WPF) app, an IOAuthAuthorizeHandler component is used to handle some of the OAuth details. Specifically, it
        //     implements AuthorizeAsync to show the login UI (generated by the server that hosts secure content) in a web control.
        //     When the user logs in successfully, cancels the login, or closes the window without continuing, the IOAuthAuthorizeHandler
        //     is responsible for obtaining the authorization from the server or raising an OperationCanceledException.
        public class OAuthAuthorize : IOAuthAuthorizeHandler
        {
            // Window to contain the OAuth UI.
            private Window? _authWindow;

            // Use a TaskCompletionSource to track the completion of the authorization.
            private TaskCompletionSource<IDictionary<string, string>> _tcs;

            // URL for the authorization callback result (the redirect URI configured for your application).
            private string _callbackUrl = "";

            // URL that handles the OAuth request.
            private string? _authorizeUrl;

            // Function to handle authorization requests, takes the URIs for the secured service, the authorization endpoint, and the redirect URI.
            public Task<IDictionary<string, string>> AuthorizeAsync(Uri serviceUri, Uri authorizeUri, Uri callbackUri)
            {
                if (_tcs != null && !_tcs.Task.IsCompleted)
                    throw new Exception("Task in progress");

                _tcs = new TaskCompletionSource<IDictionary<string, string>>();

                // Store the authorization and redirect URLs.
                _authorizeUrl = authorizeUri.AbsoluteUri;
                _callbackUrl = callbackUri.AbsoluteUri;

                // Call a function to show the login controls, make sure it runs on the UI thread for this app.
                Dispatcher dispatcher = Application.Current.Dispatcher;
                if (dispatcher == null || dispatcher.CheckAccess())
                {
                    AuthorizeOnUIThread(_authorizeUrl);
                }
                else
                {
                    Action authorizeOnUIAction = () => AuthorizeOnUIThread(_authorizeUrl);
                    dispatcher.BeginInvoke(authorizeOnUIAction);
                }

                // Return the task associated with the TaskCompletionSource.
                return _tcs.Task;
            }

            // Challenge for OAuth credentials on the UI thread.
            private void AuthorizeOnUIThread(string authorizeUri)
            {
                // Create a WebBrowser control to display the authorize page.
                WebBrowser webBrowser = new WebBrowser();

                // Handle the navigation event for the browser to check for a response to the redirect URL.
                webBrowser.Navigating += WebBrowserOnNavigating;

                // Display the web browser in a new window.
                _authWindow = new Window
                {
                    Content = webBrowser,
                    Width = 450,
                    Height = 450,
                    WindowStartupLocation = WindowStartupLocation.CenterOwner
                };

                // Set the app's window as the owner of the browser window (if main window closes, so will the browser).
                if (Application.Current != null && Application.Current.MainWindow != null)
                {
                    _authWindow.Owner = Application.Current.MainWindow;
                }

                // Handle the window closed event then navigate to the authorize url.
                _authWindow.Closed += OnWindowClosed;
                webBrowser.Navigate(authorizeUri);

                // Display the window.
                _authWindow.ShowDialog();
            }

            // Handle the browser window closing.
            private void OnWindowClosed(object? sender, EventArgs e)
            {
                // If the browser window closes, return the focus to the main window.
                if (_authWindow != null && _authWindow.Owner != null)
                {
                    _authWindow.Owner.Focus();
                }

                // If the task wasn't completed, the user must have closed the window without logging in.
                if (!_tcs.Task.IsCompleted)
                {
                    // Set the task completion source exception to indicate a canceled operation.
                    _tcs.SetCanceled();
                }

                _authWindow = null;
            }

            // Handle browser navigation (content changing).
            private void WebBrowserOnNavigating(object sender, NavigatingCancelEventArgs e)
            {
                // Check for a response to the callback url.
                const string portalApprovalMarker = "/oauth2/approval";
                WebBrowser? webBrowser = sender as WebBrowser;

                Uri uri = e.Uri;

                // If no browser, uri, or an empty url, return.
                if (webBrowser == null || uri == null || string.IsNullOrEmpty(uri.AbsoluteUri))
                    return;

                // Check for redirect.
                bool isRedirected = uri.AbsoluteUri.StartsWith(_callbackUrl) ||
                    _callbackUrl.Contains(portalApprovalMarker) && uri.AbsoluteUri.Contains(portalApprovalMarker);

                // Check if browser was redirected to the callback URL. (This indicates succesful authentication.)
                if (isRedirected)
                {
                    e.Cancel = true;

                    // Call a helper function to decode the response parameters.
                    IDictionary<string, string> authResponse = DecodeParameters(uri);

                    // Set the result for the task completion source.
                    _tcs.SetResult(authResponse);

                    // Close the window.
                    if (_authWindow != null)
                    {
                        _authWindow.Close();
                    }
                }
            }

            private static IDictionary<string, string> DecodeParameters(Uri uri)
            {
                // Create a dictionary of key value pairs returned in an OAuth authorization response URI query string.
                string answer = "";

                // Get the values from the URI fragment or query string.
                if (!string.IsNullOrEmpty(uri.Fragment))
                {
                    answer = uri.Fragment.Substring(1);
                }
                else
                {
                    if (!string.IsNullOrEmpty(uri.Query))
                    {
                        answer = uri.Query.Substring(1);
                    }
                }

                // Parse parameters into key / value pairs.
                Dictionary<string, string> keyValueDictionary = new Dictionary<string, string>();
                string[] keysAndValues = answer.Split(new[] { '&' }, StringSplitOptions.RemoveEmptyEntries);
                foreach (string kvString in keysAndValues)
                {
                    string[] pair = kvString.Split('=');
                    string key = pair[0];
                    string value = string.Empty;
                    if (key.Length > 1)
                    {
                        value = Uri.UnescapeDataString(pair[1]);
                    }

                    keyValueDictionary.Add(key, value);
                }

                // Return the dictionary of string keys/values.
                return keyValueDictionary;
            }
        }

        #endregion OAuth handler
    }
}

Add your values for the client ID (AppClientId) and for the redirect URL (OAuthRedirectUrl). These are the user authentication settings you created in the Set up authentication step.

ArcGISLoginPrompt.cs
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    internal 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 the Solution Explorer, expand the node for App.xaml, and double-click App.xaml.cs to open it.

In the App class, add an override for the OnStartup() function to call the SetChallengeHandler() method on your static ArcGISLoginPrompt class.

App.xaml.cs
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    public partial class App : Application
    {

        protected override void OnStartup(StartupEventArgs e)
        {
            base.OnStartup(e);

            // Call a function to set up the AuthenticationManager for OAuth.
            UserAuth.ArcGISLoginPrompt.SetChallengeHandler();

        }

    }
}

Save and close the App.xaml.cs file.

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.

Next, you will set up a view in your project to consume the view model.

Add a map view

A MapView control is used to display a map. You will add a map view to your project UI and wire it up to consume the map that is defined on MapViewModel.

Add required XML namespace and resource declarations.

Open MainWindow.xaml and switch to the XAML view
Inside the existing namespace declarations, add an esri XML namespace for the ArcGIS controls
Add XAML that defines a MapViewModel instance as a static resource

MainWindow.xaml
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<Window x:Class="DisplayAMap.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:DisplayAMap"
        xmlns:esri="http://schemas.esri.com/arcgis/runtime/2013"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">

    <Window.Resources>
        <local:MapViewModel x:Key="MapViewModel" />
    </Window.Resources>
Expand

Add a MapView control to MainWindow.xaml and bind it to the MapViewModel.

Add XAML that defines a MapView control named MainMapView
Use data binding to set the Map property of the control using the MapViewModel resource.

MainWindow.xaml
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    <Grid>

        <esri:MapView x:Name="MainMapView"
                      Map="{Binding Map, Source={StaticResource MapViewModel}}" />

    </Grid>
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Run the app

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 will see a map with the topographic basemap layer centered on the Santa Monica Mountains in California. Double-click, drag, and scroll the mouse wheel over the map view to explore the map.

Alternatively, you can download the tutorial solution, as follows.

Option 2: Download the solution

Click the Download solution link in the right-hand panel of the page.
Unzip the file to a location on your machine.
Open the .sln file in Visual Studio.

Since the downloaded solution does not contain authentication credentials, you must add the developer credentials that you created in the set up authentication section.

Set developer credentials in the solution

To allow your app users to access ArcGIS location services, use the developer credentials that you created in the Set up authentication step to authenticate requests for resources.

In Visual Studio, in the Solution Explorer, click App.xaml.cs to open the file.

Set the ArcGISEnvironment.ApiKey property with your API key access token.

App.xaml.cs
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        protected 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.SetChallengeHandler();

        }

Remove the code that sets up user authentication.

App.xaml.cs
Use dark colors for code blocks
        protected 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.SetChallengeHandler();

        }

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.

From the Visual Studio Solution explorer window, open the ArcGISLoginPrompt.cs file.

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.cs
Use dark colors for code blocks
    internal 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.

Remove the line of code that sets an API key access token.

App.xaml.cs
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        protected 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.SetChallengeHandler();

        }