juniorAngular
What is Angular Dependency Injection system?
Updated Apr 28, 2026
Short answer
DI provides dependencies automatically to components and services.
Deep explanation
Angular DI allows services to be injected into components, improving modularity and testability. It uses hierarchical injectors.
Real-world example
Injecting API service into components.
Common mistakes
- Providing services at wrong level.
Follow-up questions
- What is injector hierarchy?
- Why DI?