using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
 
namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        static SqlConnection cn = new SqlConnection("userid=sa;password=;database=northwind;server=localhost");
        SqlCommand cmd = new SqlCommand("select * from kkr", cn);
        SqlDataReader dr;
 
        private void button1_Click(object sender, EventArgs e)
        {
            if (cn.State = ConnectionState.Closed)
          {
                cn.Open();
                MessageBox.Show("ok");
                dr = cmd.ExecuteReader();
                label1.Text = dr.GetName(0);
                label2.Text = dr.GetName(1);
                label3.Text = dr.GetName(2);
            }
            else
                MessageBox.Show("connection is already opened:");
        }
 
        private void button2_Click(object sender, EventArgs e)
        {
            if(dr.Read()==true)
            {
 
                textBox1.Text = dr[0].ToString();
                textBox2.Text = dr[1].ToString();   
                textBox3.Text = dr[2].ToString();
            }
                else
                {
                    MessageBox.Show("No MOre Records:");
 
                }
 
 
 
        }
 
        private void label1_Click(object sender, EventArgs e)
        {
 
        }
 
 
 
        }
 
    }

if (cn.State = ConnectionState.Closed)

 if (cn.State == ConnectionState.Closed)