Dependency Injection in .NET MAUI

.NET MAUI uses the same Microsoft.Extensions.DependencyInjection container as ASP.NET Core. All service registration happens in MauiProgram.CreateMauiApp() on builder.Services. The container is built once at startup and is immutable thereafter.

When to Use

• Registering services, ViewModels, and Pages in MauiProgram.cs
• Choosing between AddSingleton, AddTransient, and AddScoped
• Wiring constructor injection for Pages and ViewModels
• Leveraging Shell navigation to auto-resolve DI-registered Pages
• Registering platform-specific service implementations with #if directives
• Designing interfaces for testable service layers

When Not to Use

• XAML data-binding syntax or compiled bindings — use the maui-data-binding skill
• Shell route registration and query parameters — use the maui-shell-navigation skill
• Mocking frameworks or test runners — use standard .NET testing tools (xUnit, NUnit, MSTest) and mocking libraries (NSubstitute, Moq)