How to use StringFormat in XAML elements?
XamlString FormattingXaml Problem Overview
I'm deep in a XAML stack of elements binding to orders.
The order date displays as e.g. "12/31/2008 12:00:00 AM".
I want it to display as e.g. "31.12.2008".
How can I do this? I have seen other stackoverflow questions mention StringFormat but they use multibinding in ways that I can't get to work.
Here is the kind of syntax I would like (this is pseudocode), simply specifying StringFormat where you need it, is this possible somehow?
<StackPanel>
<ListView ItemsSource="{Binding Orders}">
<ListView.View>
<GridView>
<GridViewColumn
Header="Order ID"
DisplayMemberBinding="{Binding Path=OrderID}"
StringFormat="{}{1:dd.MM.yyyy}"/>
<GridViewColumn
Header="Order Date"
DisplayMemberBinding="{Binding Path=OrderDate}"/>
</GridView>
</ListView.View>
</ListView>
</StackPanel>
Xaml Solutions
Solution 1 - Xaml
I haven't tested it, but I think this should work:
<GridViewColumn
Header="Order Date"
DisplayMemberBinding=
"{Binding Path=OrderDate, StringFormat='{}{0:dd.MM.yyyy}'}"/>
Solution 2 - Xaml
In general, you can look for an associated *StringFormat
dependency property. For example, all ContentControl implementations (such as Label and Tooltip) have the ContentStringFormat dependency property:
<Label
Content="{Binding Path=DateAsked}"
ContentStringFormat="{}{0:yyyy/MM/dd HH:mm:ss}" />
In your case, while the GridViewColumn has the HeaderStringFormat dependency property to go along with Header
, there is no analog for the DisplayMemberBinding
and so you will need .NET 3.5 SP1 (get it with Visual Studio 2008 SP1) or better to use the new BindingBase.StringFormat Property:
<GridViewColumn
Header="Order ID"
DisplayMemberBinding="{Binding Path=OrderID, StringFormat='{}{0:dd.MM.yyyy}'}"
/>
There are lots more examples at the blog post Trying out Binding.StringFormat.
Solution 3 - Xaml
XAML
<UserControl.Resources>
<myNamespace:DateTimeConverter x:Key="DateTimeConverter" />
</UserControl.Resources>
<GridViewColumn
DisplayMemberBinding=="{Binding Path=OrderDate, Converter={StaticResource DateTimeConverter}}"
/>
C#
public class DateTimeConverter : IValueConverter
{
public object Convert(object value,
Type targetType,
object parameter,
CultureInfo culture)
{
if (value != null)
{
return ((DateTime)value).ToString("dd.MM.yyyy");
}
else
{
return String.Empty;
}
}
public object ConvertBack(object value,
Type targetType,
object parameter,
CultureInfo culture)
{
return DateTime.Parse(value.ToString());
}
}
Solution 4 - Xaml
If you wanted to localize the date format, you can include it in your .resx file. You will have to set up your app for localization by following this guide: https://developer.xamarin.com/guides/xamarin-forms/advanced/localization/.
The resx entry:
<data name="DateFormat" xml:space="preserve">
<value>{0:dddd d MMMM H:mm}</value>
</data>
In your content page, you then include the location of the resx file
xmlns:il8n="clr-namespace:MyProject.Localization;assembly=MyProject"
And then you can use it in your binding like so:
<Label
Text = "{Binding Time, StringFormat={il8n:Translate DateFormat}}"