static private void ReturnNestedCollectionWithEntityCommand()
{
//<snippetReturnNestedCollectionWithEntityCommand>
using (EntityConnection conn =
new EntityConnection("name=AdventureWorksEntities"))
{
conn.Open();
try
{
// Create an EntityCommand.
using (EntityCommand cmd = conn.CreateCommand())
{
// Create a nested query.
string esqlQuery =
@"Select c.ContactID, c.SalesOrderHeader
From AdventureWorksEntities.Contact as c";
cmd.CommandText = esqlQuery;
// Execute the command.
using (EntityDataReader rdr =
cmd.ExecuteReader(CommandBehavior.SequentialAccess))
{
// The result returned by this query contains
// ContactID and a nested collection of SalesOrderHeader items.
// associated with this Contact.
while (rdr.Read())
{
// the first column contains Contact ID.
Console.WriteLine("Contact ID: {0}", rdr["ContactID"]);
// The second column contains a collection of SalesOrderHeader
// items associated with the Contact.
DbDataReader nestedReader = rdr.GetDataReader(1);
while (nestedReader.Read())
{
Console.WriteLine(" SalesOrderID: {0} ", nestedReader["SalesOrderID"]);
Console.WriteLine(" OrderDate: {0} ", nestedReader["OrderDate"]);
}
}
}
}
}
catch (EntityException ex)
{
Console.WriteLine(ex.ToString());
}
conn.Close();
}
//</snippetReturnNestedCollectionWithEntityCommand>
}