using System.Data.Entity.Infrastructure; public class MyEntity : IEventSource { public int Id { get; set; } public string Name { get; set; } public object[] GetKeys() { return new object[] { Id }; } public void GenerateEntityKey(DbModelBuilder modelBuilder) { modelBuilder.EntityIn this example, we have defined a class MyEntity which implements the IEventSource interface. We have defined two properties in this class - Id and Name. The GenerateEntityKey method is used to generate a unique key for the entity stored in the database. Package/library: The IEventSource GenerateEntityKey method is part of the System.Data.Entity.Infrastructure namespace in C#.() .Property(e => e.Id) .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); } }