Microsoft.Extensions.Configuration.EnvironmentVariables An environment variable based . Initializes a new instance. Initializes a new instance with the specified prefix. A prefix used to filter the environment variables. Loads the environment variables. Represents environment variables as an . Builds the for this source. The . A A prefix used to filter environment variables. Extension methods for registering with . Adds an that reads configuration values from environment variables. The to add to. The . Adds an that reads configuration values from environment variables. The to add to. Configures the source. The . Adds an that reads configuration values from environment variables with a specified prefix. The to add to. The prefix that environment variable names must start with. The prefix will be removed from the environment variable names. The .