ILogger<TCategoryName> public interface ILogger<TCategoryName> : ILogger A generic interface for logging where the category name is derived from the specified TCategoryName type name. Generally used to enable activation of a named ILogger from dependency injection. Documentation Code using System.Runtime.CompilerServices; namespace Microsoft.Extensions.Logging { public interface ILogger<[System.Runtime.CompilerServices.Nullable(2)] out TCategoryName> : ILogger { } }