using System.ComponentModel.DataAnnotations; namespace Models { public abstract class GenericMessage { protected GenericMessage(int id, User author, string description, string title, DateTime publishDate) { ID = id; Author = author; Description = description; Title = title; PublishDate = publishDate; } protected GenericMessage() { } public int ID { get; set; } public User Author { get; set; } public string Description { get; set; } [StringLength(255)] public string Title { get; set; } public DateTime PublishDate { get; set; } } }