namespace DataFieldMappingConsoleSample
{
    using System;
    using System.Collections.Generic;
    using System.Data;
    using System.Diagnostics;
    using System.Linq;
    using System.Reflection;
 
    [AttributeUsage(AttributeTargets.Property)]
    public class DataFieldMappingAttribute : Attribute
    {
        public DataFieldMappingAttribute(string fieldName)
        {
            this.FieldName = fieldName;
        }
 
        public string FieldName { get; set; }
    }
 
    public static class IDataReaderEx
    {
        public static bool TryGetOrdinal(this IDataReader reader, string name, out int ordinal)
        {
            try
            {
                ordinal = reader.GetOrdinal(name);
                return true;
            }
            catch
            {
                ordinal = int.MinValue;
                return false;
            }
        }
 
        public static IEnumerable<T> AsEnumerable<T>(this IDataReader reader)
            where T : new()
        {
            int ordinal;
            var mappings = typeof(T).GetProperties()
                                    .Where(pi => pi.GetCustomAttributes(true).Any(attribute => attribute.GetType().FullName == typeof(DataFieldMappingAttribute).FullName))
                                    .Select(pi => new Mapping() { PropertyInfo = pi, DataFieldMapping = (DataFieldMappingAttribute)pi.GetCustomAttributes(true).Where(attribute => attribute.GetType().FullName == typeof(DataFieldMappingAttribute).FullName).First() });
 
            while (reader.Read())
            {
                T t = new T();
 
                mappings.All(
                            item =>
                            {
                                if (reader.TryGetOrdinal(item.DataFieldMapping.FieldName, out ordinal))
                                {
                                    item.PropertyInfo.SetValue(t, reader[ordinal], null);
                                }
                                else
                                {
                                    Debug.WriteLine(string.Format("DataFieldMappingAttribute '{0}' not found on the reader field collection", item.DataFieldMapping.FieldName), "Warning");
                                }
 
                                return true;
                            }
                           );
 
                yield return t;
            }
        }
 
        private class Mapping
        {
            public PropertyInfo PropertyInfo { get; set; }
            public DataFieldMappingAttribute DataFieldMapping { get; set; }
        }
    }
}