Start Debugging

configuration

4 posts

2026-09-23 dotnet-10 dotnet-11 configuration

Fix: IConfiguration.Bind does not populate an array or List<T> property from appsettings.json

The binder silently skips array properties without a public setter, get-only IReadOnlyList<T>, fields and init-only members under the source generator, and it appends to defaults instead of replacing them. Measured on .NET 10.0.12 and 11 RC 1.

2026-09-18 polly resilience dotnet

Polly 8.8 Reloads a Resilience Pipeline From Your Own IOptionsMonitor

Polly 8.8.0 adds EnableReloadsWithMonitor, so a resilience pipeline can hot-reload from a feature flag or remote config monitor that is not registered in DI. A probe shows the rebuild, and one trap: context.GetOptions still reads the DI monitor and returns defaults.

2026-08-03 csharp dotnet dotnet-11

How to validate options at startup with IValidateOptions<T> in .NET 11

Implement IValidateOptions<T>, register it in DI, and chain ValidateOnStart so a bad appsettings.json kills the process instead of the first request that touches it. Covers the .NET 11 Validate<TValidator>() overload, async validation through IAsyncValidateOptions<T>, and the three places ValidateOnStart silently does nothing.

2026-05-05 errors csharp dotnet

Fix: System.InvalidOperationException: No connection string named 'DefaultConnection' could be found

If GetConnectionString returns null in .NET 11, your appsettings.json is missing the key, not copied to the build output, or the wrong environment file is being selected. Three checks fix 95% of cases.