Wpf – Changing the string format of the WPF DatePicker

datepickerwpfwpftoolkit

I need to change the string format of the DatePickerTextBox in the WPF Toolkit DatePicker, to use hyphens instead of slashes for the seperators.

Is there a way to override this default culture or the display string format?

01-01-2010

Best Answer

I have solved this problem with a help of this code. Hope it will help you all as well.

<Style TargetType="{x:Type DatePickerTextBox}">
 <Setter Property="Control.Template">
  <Setter.Value>
   <ControlTemplate>
    <TextBox x:Name="PART_TextBox"
     Text="{Binding Path=SelectedDate, StringFormat='dd MMM yyyy', 
     RelativeSource={RelativeSource AncestorType={x:Type DatePicker}}}" />
   </ControlTemplate>
  </Setter.Value>
 </Setter>
</Style>

Related Solutions

Wpf – INotifyPropertyChanged vs. DependencyProperty in ViewModel

Kent wrote an interesting blog about this topic: View Models: POCOs versus DependencyObjects.

Short summary:

DependencyObjects are not marked as serializable
The DependencyObject class overrides and seals the Equals() and GetHashCode() methods
A DependencyObject has thread affinity – it can only be accessed on the thread on which it was created

I prefer the POCO approach. A base class for PresentationModel (aka ViewModel) which implements INotifyPropertyChanged interface can be found here: http://compositeextensions.codeplex.com

WPF toolkit DatePicker change default value ‘show calendar’

OK. I found a solution by myself.

<Style TargetType="{x:Type toolkit:DatePickerTextBox}">
    <Setter Property="Text" Value="Bitte wählen" />
</Style>

Anyways, you have to be aware of the fact, that there is a DependencyProperty called Watermark which should be set in place of the Text.

The problem is that with the latest MS release (about June 2009) they made this property readonly for some unknown reason. That means, this is the only hack I made up, although there occurs a First-time exception, because the DatePicker is trying to parse the string (he supposes the text to be a Date), but normally you won't notice it.

Another possibility is to edit directly the source code from MS and override the SetWaterMark() method + add your own Dependency Property (MyWaterMark or something). But then you cannot use the provided dll. They said it will come fixed with the .NET 4 realese, let's see.

Best Answer

Related Solutions

Wpf – INotifyPropertyChanged vs. DependencyProperty in ViewModel

WPF toolkit DatePicker change default value ‘show calendar’

Related Topic