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Creating a DataReader

.NET Framework 4.5

The DataTable and DataSet classes have a CreateDataReader method that returns the contents of the DataTable or the contents of the DataSet object's Tables collection as one or more read-only, forward-only result sets.

Example

The following console application creates a DataTable instance. The example then passes the filled DataTableto a procedure that calls the CreateDataReader method, which iterates through the results contained within the DataTableReader.


private static void TestCreateDataReader(DataTable dt)
{
// Given a DataTable, retrieve a DataTableReader
// allowing access to all the tables' data:
using (DataTableReader reader = dt.CreateDataReader())
{
do
{
if (!reader.HasRows)
{
Console.WriteLine("Empty DataTableReader");
}
else
{
PrintColumns(reader);
}
Console.WriteLine("========================");
} while (reader.NextResult());
}
}

private static DataTable GetCustomers()
{
// Create sample Customers table, in order
// to demonstrate the behavior of the DataTableReader.
DataTable table = new DataTable();

// Create two columns, ID and Name.
DataColumn idColumn = table.Columns.Add("ID", typeof(int));
table.Columns.Add("Name", typeof(string));

// Set the ID column as the primary key column.
table.PrimaryKey = new DataColumn[] { idColumn };

table.Rows.Add(new object[] { 1, "Mary" });
table.Rows.Add(new object[] { 2, "Andy" });
table.Rows.Add(new object[] { 3, "Peter" });
table.Rows.Add(new object[] { 4, "Russ" });
return table;
}

private static void PrintColumns(DataTableReader reader)
{
// Loop through all the rows in the DataTableReader
while (reader.Read())
{
for (int i = 0; i < reader.FieldCount; i++)
{
Console.Write(reader[i] + " ");
}
Console.WriteLine();
}
}

The example displays the following output in the console window:

1 Mary
2 Andy
3 Peter
4 Russ

Creating a DataReader

Example

See Also

Reference

Other Resources