.NET Core  

.NET Core Advanced MCQs — Dependency Injection (DI)

1. DI in ASP.NET Core primarily helps with

A) Performance
B) Loose coupling & testability ✅
C) UI rendering
D) Deployment

2. Which lifetime creates a new instance per HTTP request?

A) Singleton
B) Scoped ✅
C) Transient
D) ThreadStatic

3. Which DI lifetime should DbContext use?

A) Singleton
B) Scoped ✅
C) Transient
D) Static

4. If a Singleton depends on a Scoped service, what can happen?

A) Faster execution
B) Memory leak ✅
C) Thread lock
D) No effect

5. Where are services registered in .NET Core?

A) Web.config
B) Program.cs ✅
C) AppSettings.json
D) StartupController.cs

Middleware MCQs

6. Middleware executes in:

A) Random order
B) Fixed pipeline sequence ✅
C) Compiler decides
D) Based on thread pool

7. Which method MUST be called in custom middleware?

A) Task.Run
B) builder.Build
C) await next()
D) UseMvc

8. Which is used to add routing?

A) app.UseAuthorization()
B) app.UseRouting() ✅
C) app.UseEndpoints()
D) app.MapControllers()

9. Middleware that runs FIRST for error handling?

A) UseAuthorization
B) UseExceptionHandler ✅
C) UseCors
D) MapEndpoints

10. Real order in ASP.NET Core pipeline?

A)

Auth → Routing → Exception

B)

Exception → Routing → Auth ✅ → Endpoint

C)

Endpoint → Auth → Exception

D)

Auth → Endpoint → Routing

Memory & Performance MCQs

11. What causes memory leaks in .NET Core most commonly?

A) No GC
B) Event handlers not unsubscribed ✅
C) Exception handling
D) Logging

12. GC collects?

A) Unmanaged memory
B) Managed memory ✅
C) Database connections
D) Threads

13. Which tool helps detect memory issues?

A) IIS Manager
B) Visual Studio Diagnostic Tools ✅
C) NuGet Manager
D) Windows Firewall

14. Purpose of IDisposable?

A) Compile code
B) Dispose unmanaged resources ✅
C) Debug logs
D) Speed up runtime

15. Best way to prevent memory leaks?

A) Never use Static
B) Use using & proper DI ✅
C) Avoid async
D) Restart server