问.NET核心中缺少EnumBuilder的解决方法

EN

    class EnumTypeBuilder
    {
        private TypeBuilder _enumTypeBuilder;

        public EnumTypeBuilder(ModuleBuilder builder, string name, TypeAttributes attributes, Type underlyingType)
        {
            _enumTypeBuilder = builder.DefineType(name, attributes | TypeAttributes.AutoLayout | TypeAttributes.AnsiClass | TypeAttributes.Sealed, typeof(System.Enum), PackingSize.Unspecified, TypeBuilder.UnspecifiedTypeSize);
            FieldBuilder valueFieldBuilder = _enumTypeBuilder.DefineField("value__", underlyingType, FieldAttributes.Public | FieldAttributes.SpecialName | FieldAttributes.RTSpecialName);
        }

        public void DefineLiteral(string name, object value)
        {
            FieldBuilder enumerationFieldBuilder = _enumTypeBuilder.DefineField(name, _enumTypeBuilder, FieldAttributes.Static | FieldAttributes.Public | FieldAttributes.Literal);
            enumerationFieldBuilder.SetConstant(value);
        }

        public Type CreateType()
        {
            return _enumTypeBuilder.CreateType();
        }
    }