1、我们在C#编程的时候，往往会用到时间控件，当然我这边用的比较多的控件是DatePicker，这个控件很好用，但是一般它会精确到年月日，具体的代码如下所示：<telerik:伊怕锱鳏RadCalendar x:Name="radCalender" Grid.Row="2" Grid.Column="1" SelectionChanged="radCalender_SelectionChanged">当然我这个控件是基于WPF开发的。
2、从上面的实例中我们可以看出来这个时间控件是精确到年月日，但在开发过程中，我们要计算某一个月的数据，某一年的数据，那么问题来了，我们没有必要去选择具体的日期了，那么具体的怎么实现呢？
3、从上图中的代码可以看出，我这里是建立一个类DatePickerCalendar，然后从这个类里面去实现选择月，和年的方法，然后前台去调用这个获取月和年的参数，来显示要选择年还是月
4、这里直接上代码了：u衡痕贤伎sing System;using System.Collections.Generic;using System.讣嘬铮篌Linq;using System.Text;using System.Windows;using System.Windows.Controls;using System.Windows.Controls.Primitives;using System.Windows.Threading;namespace Listen.Main.Common{ public class DatePickerCalendar { public static bool GetIsYear(DependencyObject obj) { return (bool)obj.GetValue(IsYearProperty); } public static void SetIsYear(DependencyObject obj, bool value) { obj.SetValue(IsYearProperty, value); } // Using a DependencyProperty as the backing store for IsYear. This enables animation, styling, binding, etc... public static readonly DependencyProperty IsYearProperty = DependencyProperty.RegisterAttached("IsYear", typeof(bool), typeof(DatePickerCalendar), new PropertyMetadata(false, new PropertyChangedCallback(OnIsMonthYearChanged))); public static readonly DependencyProperty IsMonthYearProperty = DependencyProperty.RegisterAttached("IsMonthYear", typeof(bool), typeof(DatePickerCalendar), new PropertyMetadata(OnIsMonthYearChanged)); public static bool GetIsMonthYear(DependencyObject dobj) { return (bool)dobj.GetValue(IsMonthYearProperty); } public static void SetIsMonthYear(DependencyObject dobj, bool value) { dobj.SetValue(IsMonthYearProperty, value); } private static void OnIsMonthYearChanged(DependencyObject dobj, DependencyPropertyChangedEventArgs e) { var datePicker = (DatePicker)dobj; Application.Current.Dispatcher .BeginInvoke(DispatcherPriority.Loaded, new Action<DatePicker, DependencyPropertyChangedEventArgs>(SetCalendarEventHandlers), datePicker, e); } private static void SetCalendarEventHandlers(DatePicker datePicker, DependencyPropertyChangedEventArgs e) { if (e.NewValue == e.OldValue) return; if ((bool)e.NewValue) { datePicker.CalendarOpened += DatePickerOnCalendarOpened; datePicker.CalendarClosed += DatePickerOnCalendarClosed; } else { datePicker.CalendarOpened -= DatePickerOnCalendarOpened; datePicker.CalendarClosed -= DatePickerOnCalendarClosed; } } private static void DatePickerOnCalendarOpened(object sender, RoutedEventArgs routedEventArgs) { var calendar = GetDatePickerCalendar(sender); if (GetIsYear(sender as DatePicker)) { calendar.DisplayMode = CalendarMode.Decade; } else { calendar.DisplayMode = CalendarMode.Year; } calendar.DisplayModeChanged += CalendarOnDisplayModeChanged; } private static void DatePickerOnCalendarClosed(object sender, RoutedEventArgs routedEventArgs) { var datePicker = (DatePicker)sender; var calendar = GetDatePickerCalendar(sender); datePicker.SelectedDate = calendar.SelectedDate; calendar.DisplayModeChanged -= CalendarOnDisplayModeChanged; } private static void CalendarOnDisplayModeChanged(object sender, CalendarModeChangedEventArgs e) { var calendar = (Calendar)sender; var datePicker = GetCalendarsDatePicker(calendar); bool mode = (GetIsYear(datePicker) && calendar.DisplayMode != CalendarMode.Year) || (GetIsMonthYear(datePicker) && calendar.DisplayMode != CalendarMode.Month); if (mode) return; calendar.SelectedDate = GetSelectedCalendarDate(calendar.DisplayDate); datePicker.IsDropDownOpen = false; } private static Calendar GetDatePickerCalendar(object sender) { var datePicker = (DatePicker)sender; var popup = (Popup)datePicker.Template.FindName("PART_Popup", datePicker); return ((Calendar)popup.Child); } private static DatePicker GetCalendarsDatePicker(FrameworkElement child) { var parent = (FrameworkElement)child.Parent; if (parent.Name == "PART_Root") return (DatePicker)parent.TemplatedParent; return GetCalendarsDatePicker(parent); } private static DateTime? GetSelectedCalendarDate(DateTime? selectedDate) { if (!selectedDate.HasValue) return null; return new DateTime(selectedDate.Value.Year, selectedDate.Value.Month, 1); } }}
5、然后前台去调用，这里选择的是DatePickerCalendar.IsMonthYear="True"，然后 这边就选择的是年和月，那么具体的日期就去掉了，所以我们显示出来的就是具体的年和月
6、还有如果DatePickerCalendar.IsYear="True" ，这里面我们选择的是具体的年份，那么图形直接显示的是具体的年份，这样我们去计算年数据的时候，就可以选择年份了
