`appsettings.Development.json` holds ASP.NET Core configuration for the Development runtime environment. The shared `appsettings.json` applies across environments; when the app runs in Development, its development-specific file is read afterward. Matching keys override shared values, while new keys add settings for Development only. section 2.4.2
The runtime environment can be selected with `DOTNET_ENVIRONMENT` or `ASPNETCORE_ENVIRONMENT`. For local runs, `ASPNETCORE_ENVIRONMENT` can be set in `launchSettings.json`. A Development-only setting is ignored when the app runs in another environment. section 2.4.2
Keep detailed errors in Development
In the board-game API, set `UseDeveloperExceptionPage` to `false` in `appsettings.json`, then add `"UseDeveloperExceptionPage": true` to `appsettings.Development.json`. In `Program.cs`, read the value with `app.Configuration.GetValue<bool>("UseDeveloperExceptionPage")` to choose between the developer exception page and the `/error` handler. Run in Development and trigger a test exception to check the detailed page; the shared setting remains false for other environments. section 2.4.2 section 2.4.3
{
"Logging": {
"LogLevel": {
"Default": "Information",
"Microsoft.AspNetCore": "Warning"
}
},
"UseDeveloperExceptionPage": true
}
This listing shows the Development file with its `UseDeveloperExceptionPage` override alongside logging settings. section 2.4.3
