Skip to main content
.NET Framework Class Library
DatePickerDateValidationError Event

Occurs when Text is set to a value that cannot be interpreted as a date or when the date cannot be selected.

Namespace:   System.Windows.Controls
Assembly:  PresentationFramework (in PresentationFramework.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
Syntax
Public Event DateValidationError As [%$TOPIC/cc672415_en-us_VS_110_2_0_0_0_0%](Of [%$TOPIC/cc672415_en-us_VS_110_2_0_0_0_1%])
public event [%$TOPIC/cc672415_en-us_VS_110_2_0_1_0_0%]<[%$TOPIC/cc672415_en-us_VS_110_2_0_1_0_1%]> DateValidationError
public:
 event [%$TOPIC/cc672415_en-us_VS_110_2_0_2_0_0%]<[%$TOPIC/cc672415_en-us_VS_110_2_0_2_0_1%]^>^ DateValidationError {
	void add ([%$TOPIC/cc672415_en-us_VS_110_2_0_2_0_2%]<[%$TOPIC/cc672415_en-us_VS_110_2_0_2_0_3%]^>^ value);
	void remove ([%$TOPIC/cc672415_en-us_VS_110_2_0_2_0_4%]<[%$TOPIC/cc672415_en-us_VS_110_2_0_2_0_5%]^>^ value);
}
member DateValidationError : IEvent<[%$TOPIC/cc672415_en-us_VS_110_2_0_3_0_0%]<[%$TOPIC/cc672415_en-us_VS_110_2_0_3_0_1%]>,
    [%$TOPIC/cc672415_en-us_VS_110_2_0_3_0_2%]>
<DatePicker DateValidationError="eventhandler"/>
Remarks

After the DateValidationError event occurs, if you set the DatePickerDateValidationErrorEventArgsThrowException property to true, one of the following exceptions is raised:

Exception type

Condition

FormatException

The text entered cannot be parsed to a valid date, and the exception is not suppressed.

ArgumentOutOfRangeException

The text entered parses to a date that is not selectable.

Examples

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

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 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);
<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 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
// 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;
    }
}
Version Information

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4

.NET Framework Client Profile

Supported in: 4
Platforms

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.