AsEnumerable
Allows you to treat an IDataReader from a database query as enumerable so that you can perform LINQ operations on it.
Source
using System.Collections.Generic;
using System.Data;
// A set of extension methods for IDataReader
public static class DataReaderExtensions
{
// Enumerates through the reads in an IDataReader.
public static IEnumerable<IDataRecord> AsEnumerable(this IDataReader reader)
{
while (reader.Read())
{
yield return reader;
}
}
}
Example
using (var connection = new SqlConnection("some connection string"))
using (var command = new SqlCommand("select * from products", connection))
{
connection.Open();
using (var reader = command.ExecuteReader())
{
var results = reader.AsEnumerable()
.Select(record => new Product
{
Name = (string)record["product_name"],
Id = (int)record["product_id"],
Category = (string)record["product_category"]
})
.GroupBy(product => product.Category);
}
}
Author: James Michael Hare
Submitted on: 20 okt. 2010
Language: C#
Type: System.Data.IDataReader
Views: 8626