枚举帮助方法，枚举数据注解自定义验证器

  1     /// <summary>
  2     /// 枚举辅助类
  3     /// </summary>
  4     public class EnumHelper
  5     {
  6 
  7         private static readonly Dictionary<Type, object> EnumCache = new Dictionary<Type, object>();
  8 
  9         private static readonly Dictionary<Type, object> EnumValueCache = new Dictionary<Type, object>();
 10         /// <summary>
 11         /// 取得枚举值列表
 12         /// </summary>
 13         public static List<T> GetEnumList<T>()
 14         {
 15             var t = typeof(T);
 16             if (!t.IsEnum)
 17             {
 18                 return null;
 19             }
 20             if (EnumCache.ContainsKey(t))
 21             {
 22                 return (List<T>)EnumCache[t];
 23             }
 24             var arr = Enum.GetValues(t);
 25             var values = new List<T>();
 26             var eor = arr.GetEnumerator();
 27             while (eor.MoveNext())
 28             {
 29                 values.Add((T)eor.Current);
 30             }
 31             EnumCache[t] = values;
 32             return values;
 33         }
 34 
 35         /// <summary>
 36         /// 取得枚举值列表
 37         /// </summary>
 38         public static List<int> GetEnumValueList<T>()
 39         {
 40             var t = typeof(T);
 41             return GetEnumValueList(t);
 42         }
 43 
 44         /// <summary>
 45         /// 取得枚举值列表
 46         /// </summary>
 47         public static List<int> GetEnumValueList(Type t)
 48         {
 49             if (!t.IsEnum)
 50             {
 51                 return null;
 52             }
 53 
 54             if (EnumValueCache.ContainsKey(t))
 55             {
 56                 return (List<int>)EnumValueCache[t];
 57             }
 58             var arr = Enum.GetValues(t);
 59             var values = new List<int>();
 60             var eor = arr.GetEnumerator();
 61             while (eor.MoveNext())
 62             {
 63                 // ReSharper disable once PossibleNullReferenceException
 64                 values.Add((int)eor.Current);
 65             }
 66             EnumValueCache[t] = values;
 67             return values;
 68 
 69         }
 70         
 71         /// <summary>
 72         /// 枚举包含值
 73         /// </summary>
 74         public static bool EnumIncludeValue<T>(int val)
 75         {
 76             var enums = GetEnumValueList<T>();
 77             return enums != null && enums.Contains(val);
 78         }
 79 
 80         /// <summary>
 81         /// 枚举包含值
 82         /// </summary>
 83         public static bool EnumInclude<T>(T val)
 84         {
 85             var enums = GetEnumList<T>();
 86             return enums != null && enums.Contains(val);
 87         }
 88 
 89         /// <summary>
 90         /// 转换为枚举
 91         /// </summary>
 92         public static T ParseEnum<T>(int value)
 93         {
 94             return ParseEnum<T>(value.ToString());
 95         }
 96 
 97         /// <summary>
 98         /// 转换为枚举
 99         /// </summary>
100         /// <param name="value">包含要转换的值或名称的字符串</param>
101         /// <returns>枚举</returns>
102         public static T ParseEnum<T>(string value)
103         {
104             return (T)Enum.Parse(typeof(T), value);
105         }
106 
107     }

 1     /// <summary>
 2     /// 枚举值正确性验证
 3     /// </summary>
 4     [AttributeUsage(AttributeTargets.Property)]
 5     public class EnumValueAttribute : ValidationAttribute
 6     {
 7         /// <summary>
 8         /// 是否需要验证上下文
 9         /// </summary>
10         public override bool RequiresValidationContext => true;
11 
12         /// <summary>
13         /// 是否有效
14         /// </summary>
15         /// <param name="value">要验证的枚举值</param>
16         /// <param name="validationContext">验证上下文</param>
17         /// <returns><see cref="ValidationResult"/>对象实例</returns>
18         protected override ValidationResult IsValid(object value, ValidationContext validationContext)
19         {
20             var t = value.GetType();
21             if (!t.IsEnum) { ExceptionHelper.ThrowProgramException("EnumValue只能附加到枚举属性上",UtilityErrors.ProgramNotImplement);}
22             var values = EnumHelper.GetEnumValueList(t);
23             return !values.Contains((int)value) ? new ValidationResult(FormatErrorMessage(validationContext.MemberName)) : null;
24         }
25     }