コード例 #1
0
        /// <summary>
        /// Retrieves the name of the constant in the specified enumeration that has the specified value.
        /// </summary>
        /// <param name="enumType">An enumeration type.</param>
        /// <param name="value">The value of a particular enumerated constant in terms of its underlying type.</param>
        /// <returns> A string containing the name of the enumerated constant in enumType whose value is value, or null if no such constant is found.</returns>
        /// <exception cref="ArgumentException"> enumType is not an System.Enum.  -or-  value is neither of type enumType nor does it have the same underlying type as enumType.</exception>
        public static string GetName(Type enumType, object value)
        {
            if (enumType == null)
            {
                throw new ArgumentNullException(nameof(enumType));
            }
            if (value == null)
            {
                throw new ArgumentNullException(nameof(value));
            }

            Type valueType = value.GetType();

            if (!valueType.IsEnum && !Type2.IsIntegerNumber(valueType))
            {
                throw new ArgumentException("The specified value should be enum base or an integer number", nameof(value));
            }

            int  length;
            bool isFlags;
            Type underlyingType;
            var  valuesAndNames = GetValuesAndNames(enumType, out length, out isFlags, out underlyingType);

            object numValue = Convert.ChangeType(value, underlyingType, null);

            //cycle through the enum values
            foreach (var item in valuesAndNames)
            {
                //if value matches return the name
                if (numValue.Equals(item.ValueAsNumber))
                {
                    return(item.Name);
                }
            }

            //if there is no match return null
            return(null);
        }
コード例 #2
0
        private static string InternalValuesFormat(Type enumType, object value)
        {
            int  length;
            bool isFlags;
            Type underlyingType;
            var  valuesAndNames = GetValuesAndNames(enumType, out length, out isFlags, out underlyingType)
                                  .OrderBy(a => a.ValueAsNumber)
                                  .ToArray();

            if (valuesAndNames.Length == 0)
            {
                return(value.ToString());
            }

            if (Type2.IsSignedNumber(underlyingType))
            {
                return(InternalSignedValuesFormat(enumType, value, valuesAndNames));
            }
            else
            {
                return(InternalUnsignedValuesFormat(enumType, value, valuesAndNames));
            }
        }