ADO Net Database ASP.Net Tutorial

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



    Cities and Customers


    
        
            

Find Customers' Cities


            
            
                        
            
            
        
    



File: Default.aspx.cs
using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class Default : System.Web.UI.Page
{
    protected void CityButton_Click(object sender, EventArgs e)
    {
        string connString = ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString;
        string cmdText = "SELECT DISTINCT country, city FROM customers";
        DataTable data = new DataTable();
        SqlDataAdapter adapter = new SqlDataAdapter(cmdText, connString);
        adapter.Fill(data);
        data.Columns.Add("CityCountry", typeof(string), "city + '   ('+ country + ')'");
        CityList.DataTextField = "CityCountry";
        CityList.DataSource = data;
        CityList.DataBind();
    }
}