namespace Util.Domains {
    /// <summary>
    /// 實體
    /// </summary>
    public interface IEntity {
    }

    /// <summary>
    /// 實體
    /// </summary>
    /// <typeparam name="TKey">標識型別</typeparam>
    public interface IEntity<out TKey> : IEntity {
        /// <summary>
 

        /// 標識
        /// </summary>
        TKey Id { get; }
    }
}

namespace Util.Domains {
    /// <summary>
    /// 聚合根
    /// </summary>
    public interface IAggregateRoot : IEntity {
        /// <summary>
        /// 版本號(樂觀鎖)
        /// </summary>
        byte[] Version { get
 
; set; }
    }

    /// <summary>
    /// 聚合根
    /// </summary>
    /// <typeparam name="TKey">標識型別</typeparam>
    public interface IAggregateRoot<out TKey> : IEntity<TKey>, IAggregateRoot {
    }
}

namespace Util.Domains {
    /// <summary>
    /// 聚合根
    /// </summary>
 

    /// <typeparam name="TKey">標識型別</typeparam>
    public abstract class AggregateRoot<TKey> : EntityBase<TKey>, IAggregateRoot<TKey> {
        /// <summary>
        /// 初始化聚合根
        /// </summary>
        /// <param name="id">標識</param>
        protected AggregateRoot( TKey id )
            : base( id ) {
        }

        /// <summary>
        /// 版本號(樂觀鎖)
        /// </summary>
        public byte[] Version { get; set; }
    }
}

using System;
using System.ComponentModel.DataAnnotations;
using Util.Validations;

namespace Util.Domains {
    /// <summary>
    /// 聚合根
    /// </summary>
    public abstract class AggregateRoot : AggregateRoot<Guid> {
        /// <summary>
        /// 初始化聚合根
        /// </summary>
        /// <param name="id">標識</param>
        protected AggregateRoot( Guid id ) 
            : base( id ){
        }

        /// <summary>
        /// 驗證
        /// </summary>
        protected override void Validate( ValidationResultCollection results ) {
            if ( Id == Guid.Empty )
                results.Add( new ValidationResult( "Id不能為空" ) );
        }
    }
}