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DatePicker.BlackoutDates Property

Definition

Gets or sets a collection of dates that are marked as not selectable.

public:
 property System::Windows::Controls::CalendarBlackoutDatesCollection ^ BlackoutDates { System::Windows::Controls::CalendarBlackoutDatesCollection ^ get(); };
public System.Windows.Controls.CalendarBlackoutDatesCollection BlackoutDates { get; }
member this.BlackoutDates : System.Windows.Controls.CalendarBlackoutDatesCollection
Public ReadOnly Property BlackoutDates As CalendarBlackoutDatesCollection

Property Value

A collection of dates that cannot be selected. The default value is an empty collection.

Examples

The following example creates a DatePicker that displays the dates in August 2009 and specifies that each Saturday and Sunday is not selectable.

DatePicker datePickerWithBlackoutDates = new DatePicker();

datePickerWithBlackoutDates.DisplayDateStart = new DateTime(2009, 8, 1);
datePickerWithBlackoutDates.DisplayDateEnd = new DateTime(2009, 8, 31);
datePickerWithBlackoutDates.SelectedDate = new DateTime(2009, 8, 10);

datePickerWithBlackoutDates.BlackoutDates.Add(
    new CalendarDateRange(new DateTime(2009, 8, 1), new DateTime(2009, 8, 2)));
datePickerWithBlackoutDates.BlackoutDates.Add(
    new CalendarDateRange(new DateTime(2009, 8, 8), new DateTime(2009, 8, 9)));
datePickerWithBlackoutDates.BlackoutDates.Add(
    new CalendarDateRange(new DateTime(2009, 8, 15), new DateTime(2009, 8, 16)));
datePickerWithBlackoutDates.BlackoutDates.Add(
    new CalendarDateRange(new DateTime(2009, 8, 22), new DateTime(2009, 8, 23)));
datePickerWithBlackoutDates.BlackoutDates.Add(
    new CalendarDateRange(new DateTime(2009, 8, 29), new DateTime(2009, 8, 30)));

datePickerWithBlackoutDates.DateValidationError +=
    new EventHandler<DatePickerDateValidationErrorEventArgs>(DatePicker_DateValidationError);

// root is a Panel that is defined elsewhere.
root.Children.Add(datePickerWithBlackoutDates);
Dim datePickerWithBlackoutDates As New DatePicker()

datePickerWithBlackoutDates.DisplayDateStart = New DateTime(2009, 8, 1)
datePickerWithBlackoutDates.DisplayDateEnd = New DateTime(2009, 8, 31)
datePickerWithBlackoutDates.SelectedDate = New DateTime(2009, 8, 10)

datePickerWithBlackoutDates.BlackoutDates.Add( _
    New CalendarDateRange(New DateTime(2009, 8, 1), New DateTime(2009, 8, 2)))

datePickerWithBlackoutDates.BlackoutDates.Add( _
    New CalendarDateRange(New DateTime(2009, 8, 8), New DateTime(2009, 8, 9)))

datePickerWithBlackoutDates.BlackoutDates.Add( _
    New CalendarDateRange(New DateTime(2009, 8, 15), New DateTime(2009, 8, 16)))

datePickerWithBlackoutDates.BlackoutDates.Add( _
    New CalendarDateRange(New DateTime(2009, 8, 22), New DateTime(2009, 8, 23)))

datePickerWithBlackoutDates.BlackoutDates.Add( _
    New CalendarDateRange(New DateTime(2009, 8, 29), New DateTime(2009, 8, 30)))

AddHandler datePickerWithBlackoutDates.DateValidationError, _
    AddressOf DatePicker_DateValidationError

' root is a Panel that is defined elsewhere. 
root.Children.Add(datePickerWithBlackoutDates)
<DatePicker Name="datePickerWithBlackoutDates"
            DisplayDateStart="8/1/09"
            DisplayDateEnd="8/31/09"
            SelectedDate="8/10/09"
            DateValidationError="DatePicker_DateValidationError">
  <DatePicker.BlackoutDates>
    <CalendarDateRange Start="8/1/09" End="8/2/09"/>
    <CalendarDateRange Start="8/8/09" End="8/9/09"/>
    <CalendarDateRange Start="8/15/09" End="8/16/09"/>
    <CalendarDateRange Start="8/22/09" End="8/23/09"/>
    <CalendarDateRange Start="8/29/09" End="8/30/09"/>
  </DatePicker.BlackoutDates>
</DatePicker>

The DatePicker handles the DateValidationError event, as shown in the following code. If the user enters a date that is not selectable, the example displays a message. If the user enters text that is not a valid date, an exception is thrown.

// If the text is a valid date, but a part of the 
// BlackoutDates collection, show a message.
// If the text is not a valid date, thow an exception.
private void DatePicker_DateValidationError(object sender,
                DatePickerDateValidationErrorEventArgs e)
{
    DateTime newDate;
    DatePicker datePickerObj = sender as DatePicker;

    if (DateTime.TryParse(e.Text, out newDate))
    {
        if (datePickerObj.BlackoutDates.Contains(newDate))
        {
            MessageBox.Show(String.Format("The date, {0}, cannot be selected.",
                                           e.Text));
        }
    }
    else
    {
        e.ThrowException = true;
    }
}
' If the text is a valid date, but a part of the 
' BlackoutDates collection, show a message. 
' If the text is not a valid date, thow an exception. 
Private Sub DatePicker_DateValidationError(ByVal sender As Object, _
                                           ByVal e As DatePickerDateValidationErrorEventArgs)

    Dim newDate As DateTime
    Dim datePickerObj As DatePicker = TryCast(sender, DatePicker)

    If DateTime.TryParse(e.Text, newDate) Then
        If datePickerObj.BlackoutDates.Contains(newDate) Then
            MessageBox.Show([String].Format("The date, {0}, cannot be selected.", e.Text))
        End If
    Else
        e.ThrowException = True
    End If
End Sub

The preceding example produces output that is similar to the following illustration.

DatePicker with dates that are not selectable
DatePicker with dates that are not selectable

Remarks

Dates in this collection will appear as disabled on the drop-down calendar. If the user types a date that is not selectable, the DateValidationError event occurs.

To make all past dates not selectable, you can use the AddDatesInPast method provided by the collection returned by this property.

Adding a date to this collection when it is already selected or adding a date outside the range specified by DisplayDateStart and DisplayDateEnd will cause an ArgumentOutOfRangeException.

XAML Property Element Usage

<object>  
  <object.BlackoutDates>  
    oneOrMoreCalendarDateRanges  
  </object.BlackoutDates>  
</object>  

XAML Values

oneOrMoreCalendarDateRanges
One or more object elements of type CalendarDateRange.

Applies to