ASP.NET Core Configuration & Environments

Question 1

What is the default hierarchy of configuration providers in ASP.NET Core?

Accepted Answer

appsettings.json → appsettings.{Env}.json → Environment variables → Command-line (last wins)

Answer

Later providers override earlier ones: appsettings.json → environment-specific file → env vars → command-line args.

Question 2

Which environment variable sets the current environment in ASP.NET Core?

Accepted Answer

ASPNETCORE_ENVIRONMENT

Answer

ASPNETCORE_ENVIRONMENT sets the hosting environment name, which determines which appsettings.{Env}.json file is loaded.

Question 3

How do you bind a configuration section to a strongly-typed class?

Accepted Answer

Configuration.GetSection("Key").Bind(instance)

Answer

GetSection("Key").Bind(instance) or GetSection("Key").Get<T>() maps configuration values to properties of a strongly-typed class.

Question 4

What does IOptions provide compared to IOptionsSnapshot?

Accepted Answer

IOptions is singleton and does not reload; IOptionsSnapshot reloads per-request

Answer

IOptions is a singleton that doesn't reload; IOptionsSnapshot is scoped and reflects configuration changes per request.

Question 5

Which interface provides configuration that reloads when the source file changes?

Accepted Answer

IOptionsMonitor<T>

Answer

IOptionsMonitor<T> is a singleton that fires a change notification and provides the latest configuration when the source changes.

ASP.NET Core Practice Test