C# interview questions covering testing, security, apis & reliability.
Open a question for the full answer, code and interview guidance.
Integration testing verifies that multiple application components work together correctly. Unlike a unit test, it may exercise routing, middleware, model binding, dependency injection, authentication, database access, and HTTP responses together.
These are forms of test doubles used to replace real dependencies during testing.
Passwords should never be stored as plain text and should not be encrypted with a reversible application key for normal authentication storage.
SQL injection occurs when untrusted input is treated as executable SQL syntax rather than data.
XSS occurs when untrusted content is rendered into a page in a way that allows attacker-controlled script or markup to execute in another user's browser.
A REST-style HTTP API models resources and uses standard HTTP methods and status codes consistently.
PUT generally represents replacing the state of a resource at a known URI with the supplied representation. It is normally expected to be idempotent.
An operation is idempotent when performing the same operation multiple times has the same intended effect on server state as performing it once.
Caching stores reusable data or responses so expensive work does not need to be repeated for every request.
Health checks expose application health information that infrastructure can use for monitoring, orchestration, and traffic management.