https://learn.microsoft.com/en-us/dotnet/api/microsoft.aspnetcore.mvc.actionconstraints.actionmethodselectorattribute?view=aspnetcore-2.2
ActionMethodSelectorAttribute Class (Microsoft.AspNetCore.Mvc.ActionConstraints) | Microsoft Learn
Base class for attributes which can implement conditional logic to enable or disable an action for a given request. See IActionConstraint.
classmicrosoftaspnetcoremvclearn