The items in a ResourceDictionary are not immediately processed when application code is loaded by a XAML loader. Instead, the ResourceDictionary persists as an object, and the individual values are processed only when they are specifically requested.

The ResourceDictionary class is not derived from DictionaryBase. Instead, the ResourceDictionary class implements IDictionary but relies on a Hashtable internally.

In Extensible Application Markup Language (XAML), the ResourceDictionary class is typically an implicit collection element that is the object element value of several Resources properties, when given in property element syntax. For details on implicit collections in XAML, see XAML Syntax In Detail. An exception is when you want to specify a merged dictionary; for details, see Merged Resource Dictionaries.

Another possible XAML usage is to declare a resource dictionary as a discrete XAML file, and either load it at run time with Load or include it in a (full-trust) project as a resource or loose file. In this case, ResourceDictionary can be declared as an object element, serving as the root element of the XAML. You must map the appropriate XML namespace values (default for the WPF namespace and typically x: for the XAML namespace) onto the ResourceDictionary element if you plan to use it as the root element. Then you can add child elements that define the resources, each with an x:Key value.

This example shows how to use application resources.

The following example shows an application definition file. The application definition file defines a resource section (a value for the Resources property). Resources defined at the application level can be accessed by all other pages that are part of the application. In this case, the resource is a declared style. Because a complete style that includes a control template can be lengthy, this example omits the control template that is defined within the ContentTemplate property setter of the style.

<Application.Resources>
  <Style TargetType="Button" x:Key="GelButton" >
    <Setter Property="Margin" Value="1,2,1,2"/>
    <Setter Property="HorizontalAlignment" Value="Left"/>
    <Setter Property="Template">
      <Setter.Value>


...


      </Setter.Value>
    </Setter>
  </Style>
</Application.Resources>

The following example shows a XAML page that references the application-level resource that the previous example defined. The resource is referenced by using a StaticResource Markup Extension that specifies the unique resource key for the requested resource. No resource with key of "GelButton" is found in the current page, so the resource lookup scope for the requested resource continues beyond the current page and into the defined application-level resources.

<StackPanel
  Name="root"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  >
  <Button Height="50" Width="250" Style="{StaticResource GelButton}" Content="Button 1" />
  <Button Height="50" Width="250" Style="{StaticResource GelButton}" Content="Button 2" />
</StackPanel>

.NET Framework

.NET Framework Client Profile

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Other Resources