private void btnSet_Click(object sender, EventArgs e) { MonthCalendar monthCalendar = (MonthCalendar)Controls.Find("monthCalendar", true)[0]; Chart chart = (Chart)Controls.Find("chart", true)[0]; ListBox listLocalities = (ListBox)Controls.Find("listLocalities", true)[0]; int countDays = DateTime.DaysInMonth(monthCalendar.SelectionStart.Year, monthCalendar.SelectionStart.Month); Locality locality = (Locality)listLocalities.SelectedItem; chart.Series[0].Points.Clear(); DateTime selectionDateTime = new DateTime(monthCalendar.SelectionStart.Year, monthCalendar.SelectionStart.Month, 1); for (int i = 0; i < countDays; i++) { chart.Series[0].Points.AddXY(i + 1, baseSystem.GetCountClientsByMonthLocalityDay(selectionDateTime.AddDays(i), locality)); } chart.Update(); }