Asynchronous-command-processing-using-the-callback-approach-C

ADO Net Database ASP.Net Tutorial

            <%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Configuration" %>

    protected void Page_Load(object sender, EventArgs e)
    {
        SqlConnection DBCon;
        SqlCommand Command = new SqlCommand();
        SqlAsyncResult ASyncResult;
        DBCon = new SqlConnection();
        Command = new SqlCommand();
        DBCon.ConnectionString = ConfigurationManager.ConnectionStrings["DSN_NorthWind"].ConnectionString;
        Command.CommandText = 
                "SELECT TOP 5 Customers.CompanyName, Customers.ContactName, " +
                " Orders.OrderID, Orders.OrderDate, " +
                " Orders.RequiredDate, Orders.ShippedDate " +
                " FROM Orders, Customers " +
                " WHERE Orders.CustomerID = Customers.CustomerID " +
                " ORDER BY Customers.CompanyName, Customers.ContactName ";
        Command.CommandType = CommandType.Text;
        Command.Connection = DBCon;
        DBCon.Open();
        AsyncResult = Command.BeginExecuteReader(new AsyncCallback(CBMethod), 
                                        CommandBehavior.CloseConnection);
    }
    public void CBMethod(SQLAsyncResult ar)
    {
        SqlDataReader OrdersReader;
        OrdersReader = ar.EndExecuteReader(ar);
        gvOrders.DataSource = OrdersReader;
        gvOrders.DataBind();
    }



    The Call Back Approach


    
    
            Runat="server">
        
                    DataField="CompanyName">
                    DataField="ContactName">
                    DataFormatString="{0:d}">
                    DataFormatString="{0:d}">
                    DataFormatString="{0:d}">
        
     
    

    


File: Web.config

  
                     connectionString="Data Source=localhost\SQLEXPRESS;Initial Catalog=Northwind;Integrated Security=True"
             providerName="System.Data.SqlClient" />