Question

我可能会感到厌倦，但为什么这会引发例外：

 this.SomeDatePicker.SelectedDate = DateTime.Now.Date;

同样的情况：

 this.SomeDatePicker.SelectedDate = DateTime.Now;

错误消息是：

System.ArgumentOutOfRangeException was unhandled
  Message=SelectedDate value is not valid.
Parameter name: d
  Source=PresentationFramework
  ParamName=d
  StackTrace:
       at System.Windows.Controls.Calendar.OnSelectedDateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
       at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
       at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
       at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
       at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
       at System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
       at System.Windows.Controls.DatePicker.CoerceSelectedDate(DependencyObject d, Object value)
       at System.Windows.DependencyObject.ProcessCoerceValue(DependencyProperty dp, PropertyMetadata metadata, EntryIndex& entryIndex, Int32& targetIndex, EffectiveValueEntry& newEntry, EffectiveValueEntry& oldEntry, Object& oldValue, Object baseValue, Object controlValue, CoerceValueCallback coerceValueCallback, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, Boolean skipBaseValueChecks)
       at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
       at System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
       at System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value)
       ....

Answer 1

如果您设置的日期出现在BlackoutDates中，则会引发该异常。

AddDaysInPast方法应相当于：

Add(new CalendarDateRange(DateTime.MinValue, DateTime.Today.AddDays(-1)));

因此，除非当前时间在调用AddDaysInPast和SelectedDate分配之间发生变化，否则您不应该遇到所描述的问题。

在调试中获取BlackoutDates中的完整范围并使用该信息更新您的问题，您可以使用以下内容：

string ranges = string.Join(
    Environment.NewLine,
    DatePicker.BlackoutDates.Select(r => string.Concat(r.Start, "|", r.End)));

Answer 2

如果DateTime.Now超出了由BlackoutDates中包含的DisplayDateStart和DisplayDateEnd OR定义的范围，则抛出异常。

Answer 3

查找

ArgumentOutOfRangeException：指定的日期不在DisplayDateStart和DisplayDateEnd定义的范围内，或者指定的日期在BlackoutDates集合中。

字体：http://msdn.microsoft.com/pt-br/library/system.windows.controls.datepicker.selecteddate.aspx

看看例外！

您只需要日期，时间或日期吗？

DateTime.Now.ToString("yyyy-MM-dd"); // only date

或

DateTime.Now.ToString("yyyy-MM-dd hh:mm"); // date and hour

Answer 4

谢谢JoãoAngelo，Ryan的回答和Ascension答案我能得到理想的结果：

if ( IsInmediate ) 
{
     SomeDatePicker.BlackoutDate.Clear();
     SomeDatePicker.SelectedDate = DateTime.Now;
     SomeDatePicker.BlackoutDate.AddDatesInPast();
}

Message = SelectedDate值无效

4 个答案: