ASP.NET Core Configuration & Logging 3

Question 1

What is IOptionsSnapshot<T> used for in ASP.NET Core?

Accepted Answer

To get a scoped options value that reflects configuration changes between requests

Answer

IOptionsSnapshot<T> recomputes options per request scope, allowing configuration file changes to take effect without restarting.

Question 2

Which method adds Serilog as the host logging provider in the minimal hosting model?

Accepted Answer

builder.Host.UseSerilog()

Answer

builder.Host.UseSerilog() replaces the default .NET logging with Serilog on the generic host level.

Question 3

What does the ASPNETCORE_ENVIRONMENT environment variable control?

Accepted Answer

The active environment name, affecting which appsettings and middleware are loaded

Answer

ASPNETCORE_ENVIRONMENT sets IWebHostEnvironment.EnvironmentName, switching between Development, Staging, and Production behaviors.

Question 4

What is the purpose of IConfiguration.GetConnectionString("name") in ASP.NET Core?

Accepted Answer

It retrieves the connection string from the ConnectionStrings section by name

Answer

GetConnectionString() is a shorthand for configuration.GetSection("ConnectionStrings")[name], a conventional location for connection strings.

Question 5

Which method validates options at startup and throws if the configuration is invalid?

Accepted Answer

services.AddOptions<T>().ValidateDataAnnotations().ValidateOnStart()

Answer

ValidateDataAnnotations() checks data annotation attributes, and ValidateOnStart() ensures validation occurs at app launch rather than first use.

ASP.NET Core Practice Test