added sample app for dotnet

Author: AikoBB

articles/communication-services/quickstarts/identity/entra-id-authentication-integration.md

@@ -178,6 +178,10 @@ The developer's required actions are shown in following diagram:
 > [!NOTE]
 > The following sections describe how to create `AzureCommunicationTokenCredential`.
 
+::: zone pivot="programming-language-csharp"
+[!INCLUDE [.NET](./includes/entra-id/support-entra-id-users-net.md)]
+::: zone-end
+
 ::: zone pivot="programming-language-javascript"
 [!INCLUDE [JavaScript](./includes/entra-id/support-entra-id-users-js.md)]
 ::: zone-end

articles/communication-services/quickstarts/identity/includes/entra-id/support-entra-id-users-js.md

@@ -125,7 +125,7 @@ app.get('/', async (req, res) => {
     }
 });
 ```
-Providing scopes is optional. When not specified, the .default scope is automatically used, requesting all API permissions for Communication Services Clients.
+Providing scopes is optional. When not specified, the `https://communication.azure.com/clients/.default` scope is automatically used, requesting all API permissions for Communication Services Clients.
 
 <a name='step-3-obtain-acs-access-token-of-the-entra-id-user'></a>
 

articles/communication-services/quickstarts/identity/includes/entra-id/support-entra-id-users-net.md

@@ -0,0 +1,140 @@
+---
+title: include file
+description: include file
+services: azure-communication-services
+author: aigerimb
+manager: soricos
+
+ms.service: azure-communication-services
+ms.subservice: azure-communication-services
+ms.date: 05/06/2025
+ms.topic: include
+ms.custom: include file
+ms.author: aigerimb
+---
+
+## Set up prerequisites
+
+- The latest version [.NET SDK](https://dotnet.microsoft.com/download/dotnet) for your operating system.
+- [Azure Identify SDK for .Net](https://www.nuget.org/packages/Azure.Identity) to authenticate with Microsoft Entra ID.
+- [Azure Communication Services Common SDK for .Net](https://www.nuget.org/packages/Azure.Communication.Common/) to obtain Azure Communication Services access tokens for Microsoft Entra ID user.
+
+## Final code
+Find the finalized code for this quickstart on [GitHub](https://github.com/Azure-Samples/communication-services-dotnet-quickstarts/tree/main/EntraIdUsersSupportQuickstart).
+
+## Set up
+
+### Create a new C# application
+
+In a console window (such as cmd, PowerShell, or Bash), use the `dotnet new` command to create a new console app with the name `EntraIdUsersSupportQuickstart`. This command creates a simple "Hello World" C# project with a single source file: **Program.cs**.
+
+```console
+dotnet new console -o EntraIdUsersSupportQuickstart
+```
+
+Change your directory to the newly created app folder and use the `dotnet build` command to compile your application.
+
+```console
+cd EntraIdUsersSupportQuickstart
+dotnet build
+```
+
+### Install the package
+
+While still in the application directory, install the Azure Identity and Azure Communication Services Common library for .NET package by using the `dotnet add package` command. The Azure Communication Services Common SDK version should be `1.4.0` or later.
+
+```console
+dotnet add package Azure.Identity
+dotnet add package Azure.Communication.Common
+```
+
+### Set up the app framework
+
+From the project directory:
+
+1. Open **Program.cs** file in a text editor
+1. Replace the contents of **Program.cs** with the following code:
+
+```csharp
+using Azure.Communication;
+using Azure.Identity;
+
+namespace EntraIdUsersSupportQuickstart
+{
+    class Program
+    {
+        static async Task Main(string[] args)
+        {
+            Console.WriteLine("Azure Communication Services - Obtain Access Token for Entra ID User Quickstart");
+
+            // Quickstart code goes here
+        }
+    }
+}
+```
+
+<a name='step-1-obtain-entra-user-token-via-the-identity-library'></a>
+
+### Step 1: Initialize implementation of TokenCredential from Azure Identity SDK
+
+The first step in obtaining Communication Services access token for Entra ID user is getting an Entra ID access token for your Entra ID user by using [Azure.Identity](/dotnet/api/overview/azure/identity-readme?view=azure-dotnet) SDK. The code below retrieves Microsoft Entra client ID and tenant ID from environment variables named `ENTRA_CLIENT_ID` and `ENTRA_TENANT_ID`.
+
+```csharp
+// This code demonstrates how to fetch your Microsoft Entra client ID and tenant ID from environment variables.
+string clientId = Environment.GetEnvironmentVariable("ENTRA_CLIENT_ID");
+string tenantId = Environment.GetEnvironmentVariable("ENTRA_TENANT_ID");
+
+//Initialize InteractiveBrowserCredential for use with CommunicationTokenCredential.
+var options = new InteractiveBrowserCredentialOptions
+{
+    TenantId = tenantId,
+    ClientId = clientId,
+};
+var entraTokenCredential = new InteractiveBrowserCredential(options);
+
+```
+
+### Step 2: Initialize CommunicationTokenCredential
+
+Instantiate a `CommunicationTokenCredential` with the TokenCredential created above and your Communication Services resource endpoint URI. The code below retrieves the endpoint for the resource from an environment variable named `COMMUNICATION_SERVICES_RESOURCE_ENDPOINT`.
+
+Add the following code to the `Main` method:
+
+```csharp
+// This code demonstrates how to fetch your Azure Communication Services resource endpoint URI
+// from an environment variable.
+string resourceEndpoint = Environment.GetEnvironmentVariable("COMMUNICATION_SERVICES_RESOURCE_ENDPOINT");
+
+// Set up CommunicationTokenCredential to request a Communication Services access token for a Microsoft Entra ID user.
+var entraTokenCredentialOptions = new EntraCommunicationTokenCredentialOptions(
+    resourceEndpoint: resourceEndpoint,
+    entraTokenCredential: entraTokenCredential)
+{
+    Scopes = new[] { "https://communication.azure.com/clients/VoIP" }
+};
+
+var credential = new CommunicationTokenCredential(entraTokenCredentialOptions);
+
+```
+
+Providing scopes is optional. When not specified, the `https://communication.azure.com/clients/.default` scope is automatically used, requesting all API permissions for Communication Services Clients.
+
+<a name='step-3-obtain-acs-access-token-of-the-entra-id-user'></a>
+
+### Step 3: Obtain Azure Communication Services access token for Microsoft Entra ID user
+
+Use the `GetTokenAsync` method to obtain an access token for the Entra ID user. The `CommunicationTokenCredential` can be used with the Azure Communication Services SDKs.
+
+```csharp
+// To obtain a Communication Services access token for Microsoft Entra ID call GetTokenAsync() method.
+var accessToken = await credential.GetTokenAsync();
+Console.WriteLine($"Token: {accessToken.Token}");
+```
+
+## Run the code
+
+Run the application from your application directory with the `dotnet run` command.
+
+```console
+dotnet run
+```