private void button1_Click(object sender, EventArgs e)
  {
         try
         {
      SqlConnection con = new SqlConnection();
  con.ConnectionString = "Data Source=(local);Initial Catalog=master;Integrated Security=True";
        con.Open();

        string str = "use master;" +
       "EXECUTE sp_attach_db @dbname = N'SaynaDB' , " +
         " @filename1 = N'" + System.Environment.CurrentDirectory + "\\Data\\SaynaDB.mdf'," +
         "@filename2 = N'" + System.Environment.CurrentDirectory + "\\Data\\SaynaDB_log.ldf'" ;

                SqlCommand cmd = new SqlCommand(str,con);
                cmd.ExecuteNonQuery();
                con.Close();


            catch (Exception x)
            {
                if(x.Message.IndexOf("already exists")>=0)
                else
                 MessageBox.Show(x.Message);
            }
   }