Top 100 Asp.net core Interview Questions

Here’s a comprehensive list of 100+ ASP.NET Core interview questions that cover a broad range of topics, from basic concepts to more advanced scenarios:

Basic Concepts

1. What is ASP.NET Core?
2. How does ASP.NET Core differ from ASP.NET Framework?
3. What are the main features of ASP.NET Core?
4. What is the .NET Core runtime?
5. What is Kestrel in ASP.NET Core?
6. Explain the concept of Middleware in ASP.NET Core.
7. What is the purpose of the Startup class in ASP.NET Core?
8. What is dependency injection and how is it used in ASP.NET Core?
9. Describe the role of ConfigureServices and Configure methods in the Startup class.
10. What is the difference between IServiceCollection and IServiceProvider?
11. How do you manage configuration settings in ASP.NET Core?
12. What is the purpose of appsettings.json?
13. Explain the role of IConfiguration in ASP.NET Core.
14. How do you implement logging in ASP.NET Core?
15. What is the role of Program.cs in an ASP.NET Core application?
16. What are ASP.NET Core Filters?
17. Explain how routing works in ASP.NET Core.
18. What is Razor Pages?
19. How do you use Entity Framework Core with ASP.NET Core?
20. What is a DbContext?

Intermediate Concepts

21. What are the different types of Middleware components in ASP.NET Core?
22. How do you use IOptions<T> in ASP.NET Core?
23. Explain the concept of action filters and exception filters.
24. What are tag helpers and how are they used?
25. How do you create a custom tag helper?
26. What is the purpose of IActionResult and ActionResult<T>?
27. How does ASP.NET Core handle dependency injection for controller classes?
28. Explain how to use ASP.NET Core Identity for authentication and authorization.
29. What is the purpose of Configure method in Startup.cs?
30. How does ASP.NET Core handle request and response pipelines?
31. Describe the concept of environment-specific configuration in ASP.NET Core.
32. What are ViewComponents and how are they different from partial views?
33. Explain how to implement CORS in ASP.NET Core.
34. What is SignalR and how is it used in ASP.NET Core?
35. How do you implement custom exception handling in ASP.NET Core?
36. What is a custom middleware and how do you create one?
37. How do you configure and use session state in ASP.NET Core?
38. Explain how model binding works in ASP.NET Core.
39. What is the IHost interface and how does it relate to IWebHost?
40. How do you implement custom model validation in ASP.NET Core?

Advanced Concepts

41. How do you secure an ASP.NET Core application using JWT tokens?
42. What is the role of IWebHostBuilder and IHostBuilder?
43. Explain the use of IApplicationBuilder in ASP.NET Core.
44. How do you handle background tasks in ASP.NET Core?
45. What are the different ways to perform data seeding in Entity Framework Core?
46. How do you create and use a custom IServiceCollection extension method?
47. Explain the role of ConfigureAppConfiguration in the HostBuilder.
48. How do you implement API versioning in ASP.NET Core?
49. What is the purpose of HealthChecks in ASP.NET Core?
50. How do you implement role-based authorization in ASP.NET Core?
51. What are the best practices for securing ASP.NET Core applications?
52. How do you use IDistributedCache and when is it beneficial?
53. Explain the concept of IBackgroundTask in ASP.NET Core.
54. How do you integrate third-party services or libraries into an ASP.NET Core application?
55. What are the best practices for optimizing ASP.NET Core performance?
56. How do you handle file uploads and downloads in ASP.NET Core?
57. What are ActionConstraints and how are they used in routing?
58. How do you configure and use Swagger/OpenAPI in ASP.NET Core?
59. What are DbContextOptions and how are they configured?
60. How do you implement and manage multi-tenancy in ASP.NET Core?

Web API Specific

61. What is the difference between IActionResult and ActionResult<T> in Web API?
62. How do you implement versioning for APIs in ASP.NET Core?
63. What is API Rate Limiting and how can you implement it in ASP.NET Core?
64. Explain the concept of API throttling in ASP.NET Core.
65. How do you use IHttpClientFactory to manage HTTP requests?
66. What is the role of ApiController attribute in ASP.NET Core Web API?
67. How do you handle request validation in Web API?
68. What are DataTransferObjects (DTOs) and how are they used?
69. Explain how to implement global exception handling in Web API.
70. How do you perform model validation in Web API?

Security

71. How do you configure HTTPS in ASP.NET Core?
72. What is Cross-Site Request Forgery (CSRF) and how is it mitigated in ASP.NET Core?
73. Explain the use of ASP.NET Core Data Protection API.
74. How do you implement OAuth2 and OpenID Connect in ASP.NET Core?
75. What are Claims and Roles in ASP.NET Core Identity?
76. How do you manage and configure authentication schemes in ASP.NET Core?
77. What is the purpose of Authorize attribute and how is it used?
78. Explain the role of IdentityServer4 in ASP.NET Core.
79. How do you implement and use HTTPS Redirection Middleware?
80. What are the security considerations for deploying ASP.NET Core applications?

Performance & Testing

81. How do you implement caching in ASP.NET Core?
82. What are the different types of caching available in ASP.NET Core?
83. Explain how to perform load testing on an ASP.NET Core application.
84. How do you use in-memory caching vs distributed caching?
85. What is the role of BenchmarkDotNet in performance testing?
86. How do you use xUnit for testing ASP.NET Core applications?
87. Explain the concept of integration testing in ASP.NET Core.
88. How do you mock dependencies in unit tests for ASP.NET Core?
89. What are Mock and Fake objects and how are they used in testing?
90. How do you test Web API endpoints in ASP.NET Core?

Deployment & DevOps

91. What are the different ways to deploy an ASP.NET Core application?
92. How do you configure environment variables in ASP.NET Core?
93. What is Docker and how is it used with ASP.NET Core?
94. Explain the role of docker-compose in deploying ASP.NET Core applications.
95. How do you use CI/CD pipelines with ASP.NET Core?
96. What is Azure App Service and how do you deploy ASP.NET Core applications to it?
97. How do you implement logging and monitoring for ASP.NET Core applications?
98. What are the considerations for scaling ASP.NET Core applications?
99. How do you use Azure Key Vault with ASP.NET Core for secret management?
100. What are the best practices for deploying ASP.NET Core applications securely?

Miscellaneous

101. What are the differences between IApplicationBuilder.Use and IApplicationBuilder.UseMiddleware?
102. How do you use IServiceScopeFactory for scoped service resolution?
103. What is the role of ServiceLifetime in ASP.NET Core dependency injection?
104. How do you use ConfigurationBuilder to build configuration settings?
105. Explain the concept of Dynamic and ExpandoObject in ASP.NET Core.

Feel free to adjust the list according to your specific needs or the focus of the interview. These questions cover a wide range of topics and should help in preparing for an ASP.NET Core interview.