/// <summary>
        /// DataGridView fill Sample 
        /// </summary>
        /// <param name="connection_str"></param>
        public void Run(string connection_str)
        {
            OleDbConnection con = new OleDbConnection(connection_str);  //create connection
            con.Open();
            OleDbTransaction trans = con.BeginTransaction();            //begin transaction 
            //create command
            OleDbCommand cmd = new OleDbCommand("select * from employee", con, trans);

            //create DataGridView and its DataSource
            DataGridView gv = new DataGridView();
            DataTable tbl = new DataTable("source"); 
            //fill DataTable
            OleDbDataAdapter adapter = new OleDbDataAdapter(cmd);               
            adapter.Fill(tbl);

            gv.DataSource = tbl; 
            
            //Display DataGridView
            Form f = new Form();
            f.Controls.Add(gv);
            gv.Dock = DockStyle.Fill;
            f.ShowDialog(); 

            //finaliaze
            trans.Commit();
            con.Close(); 
        }