通过用户登陆消息类，来学习面向对象的实体统一接口和验证统一接口

namespace Entity
{
/// <summary>
/// 用户登录消息
/// </summary>
public class UserLoginMessage : IEntity
{
List<string> message = new List<string>();
/// <summary>
/// 列表
/// </summary>
public List<string> List
{
get { return this.message; }
}

public IDataEntity Entity { get; set; }

#region IEntity 成员

public bool IsValid
{
get { return this.message.Count == 0; }
}

public IEnumerable<RuleViolation> GetRuleViolations()
{
throw new Exception("不提供本方法");
}

#endregion

}
}

namespace Entity
{
/// <summary>
/// 模型接口,与数据库无关
/// </summary>
public interface IEntity
{
/// <summary>
/// 数据验证(是否成功)
/// </summary>
bool IsValid { get; }
/// <summary>
/// 获取验证失败的信息枚举,它使用了简单的迭代器,如果GetRuleViolations有错误则返回假
/// </summary>
/// <returns></returns>
IEnumerable<RuleViolation> GetRuleViolations();

}
}

namespace Entity
{
/// <summary>
/// 数据库对象统一协调接口
/// </summary>
public interface IDataEntity
{

}
}