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The C# Station ADO.NET Tutorial
http://www.csharp-station.com/Tutorials/AdoDotNet/Lesson02.aspx
Listing 1. Using a SqlConnection
using System;
using System.Data;
using System.Data.SqlClient;
/// <summary>
/// Demonstrates how to work with SqlConnection objects
/// </summary>
class SqlConnectionDemo
{
static void Main()
{
// 1. Instantiate the connection
SqlConnection conn = new SqlConnection(
"Data Source=(local);Initial Catalog=Northwind;Integrated Security=SSPI");
SqlDataReader rdr = null;
try
{
// 2. Open the connection
conn.Open();
// 3. Pass the connection to a command object
SqlCommand cmd = new SqlCommand("select * from Customers", conn);
//
// 4. Use the connection
//
// get query results
rdr = cmd.ExecuteReader();
// print the CustomerID of each record
while (rdr.Read())
{
Console.WriteLine(rdr[0]);
}
}
finally
{
// close the reader
if (rdr != null)
{
rdr.Close();
}
// 5. Close the connection
if (conn != null)
{
conn.Close();
}
}
}
}