What are filters in ASP.NET Core?

Updated Apr 28, 2026

Short answer

Filters run code before or after controller actions.

Deep explanation

Filters provide cross-cutting concerns like authorization, logging, and exception handling. Types include Action, Authorization, and Exception filters.

Real-world example

Logging request details before execution.

Common mistakes

  • Using filters instead of middleware incorrectly.

Follow-up questions

  • What is the difference between filters and middleware?
  • What is an exception filter?

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