using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string qry = @"select * from s Condition";
            SqlConnection cnn = new SqlConnection(@"Data Source=192.168.0.111;Initial Catalog=db1;Persist Security Info=True;User ID=ali;password=aaazzz");
            cnn.Open();
            if(textBox1.Text!="")
                qry = qry.Replace("Condition","where Sname like '"+ textBox1.Text+"%'");
            SqlCommand cmd = new SqlCommand(qry,cnn);
            
            SqlDataReader dr;
            dr = cmd.ExecuteReader();
            listBox1.Items.Clear();
            while (dr.Read())
            {
               listBox1.Items.Add(dr["Sname"].ToString());
            }
            cnn.Close();
        }

        private void textBox1_TextChanged(object sender, EventArgs e)
        {
            button1_Click(sender, e);
        }
    }
}