Unity VContainer - High-Performance DI for Unity

Overview

VContainer is a high-performance IoC container for Unity, providing dependency injection patterns for testable and maintainable code.

Core Topics:

• Constructor and method injection

• Service registration patterns (Singleton, Transient, Scoped)

• LifetimeScope hierarchies

• MonoBehaviour injection

• Factory patterns with DI

• Testing with mocks

Foundation Required: unity-csharp-fundamentals (TryGetComponent, FindAnyObjectByType, null-safe coding)

Learning Path: DI fundamentals → VContainer basics → Advanced patterns → Testing

Quick Start

using VContainer; using VContainer.Unity;

// Define service interface public interface IPlayerService { void Initialize(); }

// Implement service public class PlayerService : IPlayerService { public void Initialize() => Debug.Log("Player initialized"); }

// Setup LifetimeScope public class GameLifetimeScope : LifetimeScope { protected override void Configure(IContainerBuilder builder) { builder.Register<IPlayerService, PlayerService>(Lifetime.Singleton); builder.RegisterComponentInHierarchy<PlayerController>(); } }

// Inject into MonoBehaviour public class PlayerController : MonoBehaviour { [Inject] private readonly IPlayerService mPlayerService;

void Start() => mPlayerService.Initialize();

}

Key Concepts

Lifetime Scopes

• Singleton: One instance per container

• Transient: New instance every resolve

• Scoped: One instance per scope

Injection Types

• Constructor Injection: Preferred for required dependencies

• Method Injection: For optional dependencies

• Property/Field Injection: Use [Inject] attribute

Reference Documentation

VContainer Best Practices

Core DI patterns:

• Registration patterns and lifetime management

• LifetimeScope hierarchies

• Testing with mock dependencies

VContainer Integration Patterns

Advanced integrations:

• MVVM with reactive properties

• Cross-framework integration patterns

Best Practices

• Register interfaces: Loose coupling and testability

• Constructor injection first: Explicit dependencies

• Avoid Service Locator: Don't resolve in Update loops

• Test with mocks: Use ContainerBuilder in tests

• Clear hierarchies: Root → Scene → Local scopes