private void rbMonth_Click(object sender, EventArgs e) { dtpFrom.Enabled = false; dtpTo.Enabled = false; btnFillter.Enabled = false; chartRevenue.Series["Doanh Thu"].ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Spline; chartRevenue.DataSource = Revenue.GetTotalPriceByMonth(); chartRevenue.Series["Doanh Thu"].YValueMembers = "price"; chartRevenue.Series["Doanh Thu"].YValueType = System.Windows.Forms.DataVisualization.Charting.ChartValueType.String; chartRevenue.Series["Doanh Thu"].XValueMember = "time"; chartRevenue.Series["Doanh Thu"].XValueType = System.Windows.Forms.DataVisualization.Charting.ChartValueType.String; }