/// <summary>/// 代参数的/// </summary>/// <param name="userID"></param>/// <param name="userName"></param>public User_Info(int userID, string userName){this.UserID = UserID;this.UserName = UserName;}/// <summary>/// 不代参数，但可以为其它构造方法传参数值的/// </summary>public User_Info() : this(1, "test") { }

   [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = false)]public class EmailAttribute : EntityValidationAttribute{/// <summary>/// 返回指定格式的错误/// </summary>/// <param name="messageType"></param>/// <param name="args"></param>public EmailAttribute(MessageType messageType, params object[] args) :base(messageType, args) { }/// <summary>/// 自定义的错误/// </summary>/// <param name="errMessage">错误说明</param>public EmailAttribute(string errMessage): base(errMessage) { }

 1     /// <summary>
 2     /// 通用验证基类
 3     /// </summary>
 4     public abstract class EntityValidationAttribute : ValidationAttribute
 5     {
 6         #region Constructors
 7         /// <summary>
 8         /// 定义系统某种规则的错误消息
 9         /// </summary>
10         /// <param name="messageId"></param>
11         /// <param name="args"></param>
12         public EntityValidationAttribute(MessageType messageId, params object[] args) :
13             base(() => MessageManager.Current.GetMessage(messageId, args)) { }
14
15         /// <summary>
16         /// 支持自定义的错误消息
17         /// </summary>
18         /// <param name="errMessage"></param>
19         public EntityValidationAttribute(string errMessage) : base(errMessage) { }
20         #endregion