database connectivity

Can you elaborate where and what is a problem...

post your code

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 listbox
{
  public partial class Form1 : Form
  {
  SqlConnection con = new SqlConnection(@"server = HOME-SAT/SQLEXPRESS;data source = .; initial catalog = test; user id=sa;pwd =pintu ;integrated security = SSPI");
  SqlCommand com;
  SqlDataAdapter sqlda;
  DataSet ds;
  string str;
  DataTable dt;

  public Form1()
  {
  InitializeComponent();
  }

  private void Form1_Load(object sender, EventArgs e)
  {
  listboxbind();
  }

  private void listboxbind()
  {
  con.Open();
  str = "select * from employee";
  com = new SqlCommand(str, con);
  sqlda = new SqlDataAdapter(com);
  ds = new DataSet();
  sqlda.Fill(ds, "employee");
  dt = ds.Tables["employee"];
  listBox1.DisplayMember = "empid";
  listBox1.ValueMember = "empname";
  listBox1.DataSource = ds.Tables["employee"];
  con.Close();
  }
 
  }
}