Azure Active Directory authentication in .NET MAUI

Hello!

Today, we will create a small mobile application, which requires user authentication, using .NET MAUI.

I hope you already have a valid environment. Read this article on how to set up .NET MAUI.

If you don't have an Azure Active Directory, watch this video on how to set it up:

And Azure Active Directory (B2C):

So let's start!

1. Create a new .NET MAUI project.

2. Install Microsoft.Identity.Client package:
   

If the library doesn't work on iOS/MacCatalyst, you can still use .NET MAUI WebAuthenticator.

3. Create Constants class:

4. Then modify manifest files.
   For Android open AndroidManifest.xml and add the next activity to the application:

Pay attention that data android:scheme starts with msal.

For iOS add the following code to the Info.plist:

It allows the app to correctly work with Microsoft Authenticator if a user has MFA enabled.

5. We need to override some methods to receive a callback from the identity server.

For Android open Android/MainActivity.cs and override OnActivityResult method:

You also need to set the activity attribute Exported = true.

For iOS open iOS/AppDelegate.cs and override OpenUrl method:

6. It's time to create our AuthService:

7. Now we can prepare the UI to use our AuthService.
   Add login button to your XAML and add Clicked event handler:

We are done. Start the application and check the result.

The full code can be found on GitHub.

MauiAuth Blazor sample GitHub.