XAML namespace (x:) language features

[This article is for Windows 8.x and Windows Phone 8.x developers writing Windows Runtime apps. If you’re developing for Windows 10, see the latest documentation]

This section provides reference information for the XAML language features as implemented for Windows Runtime.

In this section

Topic	Description
x:Class attribute	Configures XAML compilation to join partial classes between markup and code-behind. The code partial class is defined in a separate code file, and the markup partial class is created by code generation during XAML compilation.
x:FieldModifier attribute	Modifies XAML compilation behavior, such that fields for named object references are defined with public access rather than the private default behavior.
x:Key attribute	Uniquely identifies elements that are created and referenced as resources, and which exist within a ResourceDictionary.
x:Name attribute	Uniquely identifies object elements for access to the instantiated object from code-behind or general code. Once applied to a backing programming model, x:Name can be considered equivalent to the variable holding an object reference, as returned by a constructor.
x:Null markup extension	Specifies null as a value for a property being set through a XAML attribute.
x:Uid directive	Provides a unique identifier for markup elements. For Windows Runtime XAML, this unique identifier is used by XAML localization processes and tools, such as using resources from a .resw resource file.
XAML intrinsic data types	Lists language-level support in XAML for the Windows Runtime for certain data types in the common language runtime (CLR) and in other programming languages such as C++.