using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

using System.Data.SqlClient;    // Using Sql classes
using System.Web.Configuration; // Using web.config file

public partial class Lec7_Intro_ADONet_ReadingDatabase : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        SqlConnection connection;
        SqlCommand command;
        SqlDataReader reader;

        try
        {
            // Connect to the database using the connection string in the web.config file
            connection = new SqlConnection(WebConfigurationManager.ConnectionStrings["DatabaseConnectionString"].ConnectionString);

            // Create an SELECT Sql statement
            command = new SqlCommand("SELECT * FROM Student", connection);

            using (connection)
            {
                // Open the connection
                connection.Open();

                // Execute the command, the records are returned in an SqlDataReader object
                reader = command.ExecuteReader();

                // Have an rows been returned?
                if (reader.HasRows)
                {
                    DataTable table = new DataTable();
                    
                    // Load the DataTable with the rows from
                    // the SqlDataReader and put it into the
                    // GridView to display it.
                    table.Load(reader);
                    gridView1.DataSource = table;
                    gridView1.DataBind();
                }
                else
                {
                    statusLabel.Text = "No matching row found";
                }

                // Close the connection
                connection.Close();
            }
        }
        catch
        {
            statusLabel.Text = "An error occurred";
        }
    }
}