Copy a DataTable

we can do copy of datatable with the help of copy();

    private void button1_Click(object sender, EventArgs e)
        {
            OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\\student.mdb");
            con.Open();
         OleDbCommand cmd =new OleDbCommand("select * from marks", con);
            DataTable tb = new DataTable();
            tb.Load(cmd.ExecuteReader(CommandBehavior.CloseConnection));
            DataTable copytable = tb.Copy();
            tb = null;
            dataGridView1.DataSource = copytable;

            
        }