ContentControl.ContentStringFormat Property

ContentStringFormat can be a predefined, composite, or custom string format. For more information about string formats, see Formatting Types. If you set the ContentTemplate or ContentTemplateSelector property of a ContentControl, the ContentStringFormat property is ignored.

The following example specifies the format of DateTime objects by setting the ContentStringFormat property in a Style and applying the Style to two Label objects, which inherit from ContentControl.

<StackPanel
  xmlns:sys="clr-namespace:System;assembly=mscorlib">

  <StackPanel.Resources>
    <Style x:Key="DateLabel" TargetType="Label">
      <Setter Property="ContentStringFormat" Value="dddd – d - MMMM"/>
    </Style>
  </StackPanel.Resources>

  <!--The results when the default culture is en-US
      is March 4, 2005.-->
  <Label Style="{StaticResource DateLabel}">
    <sys:DateTime>2004/3/4 13:6:55</sys:DateTime>
  </Label>

  <Label Style="{StaticResource DateLabel}">
    <x:Static Member="sys:DateTime.Now"/>
  </Label>

</StackPanel>

.NET Framework

.NET Framework Client Profile

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.

Reference