Once you configure your function app, you need to read the values stored in it.
Reading the values contained in the settings is automatic for triggers and bindings in the sense that the infrastructure provides the INameResolver interface used by them to access these values. For more information, refer to Chapter 2, Customizing Your Azure Functions.
However, sometimes you need to access the setting values from the code of your Azure Functions. To do this, you can use the configuration support provided by .NET Core.
The following extension method extends the ExecutionContext class to provide the values configured in the settings:
public static IEnumerable<KeyValuePair<string, string>> GetConfigurations(this ExecutionContext context)
{
if (context == null)
throw new NullReferenceException(nameof(context));
...