protected void Button1_Click(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection("user id=sa;password=vubrain;database=raghu;data source=vubrain4");
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "update userlogin set loginname='"+t5.Text+"',loginaddress='"+tb1.Text+"' where loginuser=loginuser";
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
       }