ASP.NET Core environment
The ASP.NET Core environment is a named runtime setting, commonly specified by ASPNETCORE_ENVIRONMENT, that identifies the hosting context and controls environment-specific behavior and configuration.
Building Web APIs with ASP.NET Core
ASPNETCORE_ENVIRONMENT is an environment variable that specifies the runtime environment in which an ASP.NET Core application runs.
- How it is used
- Selects runtime-specific configuration and API behavior for development, testing, or production.
- How deep it goes
- Walks through local setup, configuration overrides, and middleware testing; defers production-server setup.
- Examples
- Uses Development launch profiles and a throwing /error/test endpoint to compare developer and production-style error responses.
- What you can do after
- Operate/configure it by setting a local launch profile, overriding development settings, and verifying the selected exception handler.
Read how Building Web APIs with ASP.NET Core explains ASP.NET Core environment →
ASP.NET Core in Action, 3e
ASPNETCORE_ENVIRONMENT is an environment variable that identifies the current ASP.NET Core hosting environment.
- How it is used
- Selects environment-specific application behavior and configuration across development, staging, and production deployments.
- How deep it goes
- Defines variable loading, precedence, defaults, helper checks, and environment-specific files, but does not detail broader application customization.
- Examples
- Uses Development, Staging, Production, launchSettings.json, and appsettings.Production.json as concrete environment examples.
- What you can do after
- Operate/configure an application by setting its hosting environment and selecting matching configuration files.
Read how ASP.NET Core in Action, 3e explains ASP.NET Core environment →
Related concepts
- environment variablekind of · An environment variable is a named value supplied through an operating-system or process environment and made available to programs for runtime configuration or information.
- appsettings.Development.jsonconfigures · appsettings.Development.json is an ASP.NET Core environment-specific JSON configuration file whose settings apply when the Development environment is active.
- IHostEnvironmentconfigures · IHostEnvironment is the .NET abstraction that exposes information about an application's current hosting environment and content root.
- environmentconfigures · An environment is the external context, including its entities and conditions, in which a system, process, or agent exists or operates.
- JavaScript runtimeconfigures · A JavaScript runtime is an execution environment that runs JavaScript code and provides the language engine and host APIs needed to interact with its platform.
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