EF7 FromReader.cs

public static class DbSetExtensions
{
    public static async Task<IReadOnlyList<T>> FromReaderAsync<T>(this DbSet<T> set, DbDataReader reader) where T : class
    {
        var r = new List<T>();
    
        var materializer = new DbDataReaderMaterializer<T>(set);
        while (await reader.ReadAsync())
            r.Add(materializer.Materialize(reader));
    
        return r.AsReadOnly();
    }
    
    public static IReadOnlyList<T> FromReader<T>(this DbSet<T> set, DbDataReader reader) where T : class
    {
        var r = new List<T>();
    
        var materializer = new DbDataReaderMaterializer<T>(set);
        while (reader.Read())
            r.Add(materializer.Materialize(reader));
    
        return r.AsReadOnly();
    }
    
    
    private struct DbDataReaderMaterializer<T>
    {
        private readonly Func<ValueBuffer, T> materializer;
        private readonly IRelationalValueBufferFactory valueBufferFactory;
    
        public DbDataReaderMaterializer(IInfrastructure<IServiceProvider> accessor)
        {
            var valueBufferParameter = Expression.Parameter(typeof(ValueBuffer));
            materializer = Expression.Lambda<Func<ValueBuffer, T>>(
                accessor.GetService<IEntityMaterializerSource>().CreateMaterializeExpression(
                    accessor.GetService<IModel>().FindEntityType(typeof(T)),
                    valueBufferParameter),
                valueBufferParameter).Compile();
    
            valueBufferFactory = accessor.GetService<IRelationalValueBufferFactoryFactory>().Create(new[] { typeof(T) }, null);
        }
    
        public T Materialize(DbDataReader currentRecord)
        {
            return materializer.Invoke(valueBufferFactory.Create(currentRecord));
        }
    }
}