Fire-a-database-asynchronous-operation-and-then-proceeds-up-to-the-point-where-results-are-required

ADO Net Database ASP.Net Tutorial


            <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" 
    Inherits="Default" %>



    Non-blocking Commands




File: Default.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;
using System.Web;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class Default : System.Web.UI.Page
{
    protected void Button1_Click(object sender, EventArgs e)
    {
        string connString = "Async=true;SERVER=(local);DATABASE=northwind;Trusted_Connection=yes;";
        using (SqlConnection conn = new SqlConnection(connString))
        {
            SqlCommand cmd = new SqlCommand("SELECT lastname,firstname FROM employees", conn);
            conn.Open();
            IAsyncResult iar = cmd.BeginExecuteReader();
            SqlDataReader reader = (SqlDataReader) cmd.EndExecuteReader(iar);
            ProcessData(reader);
        }
    }
    protected void ProcessData(SqlDataReader reader)
    {
        StringBuilder sb = new StringBuilder("");
        while (reader.Read())
            sb.AppendFormat("{0}, {1}
", reader[0], reader[1]);
        reader.Close();
        Results.Text = sb.ToString();
    }
}