How To Implement HttpClient in C# (4 Ways)

HttpClient in .NET simplifies calling REST APIs by sending HTTP requests and receiving responses. It supports GET, POST, PUT, and DELETE methods with async operations. Use HttpClientFactory for efficient resource management and dependency injection. Proper implementation ensures scalability, performance, and cleaner API communication in modern applications.

IHttpClientFactory(Basic Factory)

• Centralized Creation – Provides a single place to configure and create HttpClient instances.
• Handler Reuse – Manages underlying HttpMessageHandler lifetimes, preventing socket exhaustion.
• Typed Clients – Supports strongly typed clients for better readability and dependency injection.
• Configuration per Client – Allows different named or typed clients with custom settings.
• Improved Testability – Makes HttpClient easier to mock and unit test.
• Best Practice in .NET Core/9+ – Recommended way to use HttpClient instead of manually instantiating.

Named HttpClient

• Custom Configuration – Allows you to configure each HttpClient instance with different settings like base URL, headers, or timeouts.
• Centralized Setup – Configuration is defined once in Program.cs or Startup.cs and reused across the app.
• Dependency Injection – Named clients are injected via constructor using their registered name.
• Improves Readability – Makes it clear which client is being used for which external API.
• Prevents Duplication – Avoids repeating the same configuration logic in multiple places.
• Scalable Design – Perfect for apps consuming multiple APIs with unique configurations.

Typed HttpClient

• Strongly Typed – Encapsulates HttpClient in a custom class, exposing domain-specific methods (e.g., GetUsersAsync).
• Dependency Injection Support – Registered and injected via IHttpClientFactory, ensuring proper lifetime management.
• Configuration Ready – Base address, headers, and policies can be configured in Program.cs or Startup.cs.
• Testability – Easy to mock in unit tests since the typed client is an interface/class abstraction.
• Encapsulation – Keeps API logic and request handling in one place, promoting cleaner and reusable code.
• *Resilience *– Supports integration with Polly for retries, circuit breakers, and timeouts.

Refit HttpClient

• Declarative API Calls – Define REST endpoints as C# interfaces, and Refit generates the implementation.
• Strongly Typed – Eliminates manual HttpClient boilerplate with typed methods and models.
• Async by Default – All methods return Task or Task for non-blocking calls.
• Built-In Serialization – Handles JSON (or other formats) automatically using libraries like Newtonsoft.Json or System.Text.Json.
• Integration with DI – Works smoothly with IHttpClientFactory and dependency injection in .NET.
• Cleaner Code – Reduces repetitive request/response handling, making codebase more maintainable.

Conclusion

Each approach to implementing HttpClient—basic usage, HttpClientFactory, typed clients, and third-party libraries like Refit—has its own strengths. The right choice depends on your project’s needs. For small apps, a simple HttpClient works; for scalable, testable, and maintainable solutions, prefer HttpClientFactory or typed clients.