private void LoadChart()
{
DataTable dt = ThongKe.LoadDuLieu();
chart1.DataSource = dt;
chart1.ChartAreas["ChartArea1"].AxisX.Title = "Tên Trang";
chart1.ChartAreas["ChartArea1"].AxisY.Title = "Số bài";
chart1.Series["Trang"].XValueMember = "NameRoot";
chart1.Series["Trang"].YValueMembers = "soluong";
}