public static List<T> ToList<T>(IDataReader reader)
{//实例化一个List<>泛型集合List<T> DataList = new List<T>();PropertyInfo[] properties = typeof(T).GetProperties().Union(typeof(T).BaseType.GetProperties()).ToArray();while (reader.Read()){T RowInstance = Activator.CreateInstance<T>();//动态创建数据实体对象//通过反射取得对象所有的Propertyforeach (PropertyInfo Property in properties){try{//取得当前数据库字段的顺序int Ordinal = reader.GetOrdinal(Property.Name);if (reader.GetValue(Ordinal) != DBNull.Value){//将DataReader读取出来的数据填充到对象实体的属性里Property.SetValue(RowInstance, Convert.ChangeType(reader.GetValue(Ordinal), Property.PropertyType), null);}}catch{break;}}DataList.Add(RowInstance);}return DataList;
}

    public class IDataReaderEntityBuilder<Entity>{private static readonly MethodInfo getValueMethod = typeof(IDataRecord).GetMethod("get_Item", new Type[] { typeof(int) });private static readonly MethodInfo isDBNullMethod = typeof(IDataRecord).GetMethod("IsDBNull", new Type[] { typeof(int) });private delegate Entity Load(IDataRecord dataRecord);private Load handler;private IDataReaderEntityBuilder() { }public Entity Build(IDataRecord dataRecord) { return handler(dataRecord); }public static IDataReaderEntityBuilder<Entity> CreateBuilder(IDataRecord dataRecord){IDataReaderEntityBuilder<Entity> dynamicBuilder = new IDataReaderEntityBuilder<Entity>();DynamicMethod method = new DynamicMethod("IDataReaderDynamicCreateEntity", typeof(Entity), new Type[] { typeof(IDataRecord) }, typeof(Entity), true);ILGenerator generator = method.GetILGenerator();LocalBuilder result = generator.DeclareLocal(typeof(Entity));generator.Emit(OpCodes.Newobj, typeof(Entity).GetConstructor(Type.EmptyTypes));generator.Emit(OpCodes.Stloc, result);var properties = typeof(Entity).GetProperties();for (int i = 0; i < dataRecord.FieldCount; i++){PropertyInfo propertyInfo = typeof(Entity).GetProperty(properties.FirstOrDefault(x=>x.Name.ToUpper().Equals(dataRecord.GetName(i)))?.Name);Label endIfLabel = generator.DefineLabel();if (propertyInfo != null && propertyInfo.GetSetMethod() != null){generator.Emit(OpCodes.Ldarg_0);generator.Emit(OpCodes.Ldc_I4, i);generator.Emit(OpCodes.Callvirt, isDBNullMethod);generator.Emit(OpCodes.Brtrue, endIfLabel);generator.Emit(OpCodes.Ldloc, result);generator.Emit(OpCodes.Ldarg_0);generator.Emit(OpCodes.Ldc_I4, i);generator.Emit(OpCodes.Callvirt, getValueMethod);generator.Emit(OpCodes.Unbox_Any, propertyInfo.PropertyType);generator.Emit(OpCodes.Callvirt, propertyInfo.GetSetMethod());generator.MarkLabel(endIfLabel);}}generator.Emit(OpCodes.Ldloc, result);generator.Emit(OpCodes.Ret);dynamicBuilder.handler = (Load)method.CreateDelegate(typeof(Load));return dynamicBuilder;}}

public static List<T> ReaderToEntity<T>(IDataReader reader)
{//实例化一个List<>泛型集合List<T> list = new List<T>();var builder = IDataReaderEntityBuilder<T>.CreateBuilder(reader);while (reader.Read()){var entity = builder.Build(reader);list.Add(entity);}return list;
}