FrameworkElement.Name Property

Definition

Namespace:

System.Windows

Assembly:

PresentationFramework.dll

Gets or sets the identifying name of the element. The name provides a reference so that code-behind, such as event handler code, can refer to a markup element after it is constructed during processing by a XAML processor.

public:
 property System::String ^ Name { System::String ^ get(); void set(System::String ^ value); };

[System.Windows.Localizability(System.Windows.LocalizationCategory.NeverLocalize)]
public string Name { get; set; }

[<System.Windows.Localizability(System.Windows.LocalizationCategory.NeverLocalize)>]
member this.Name : string with get, set

Public Property Name As String

Property Value

String

The name of the element. The default is an empty string.

Implements

Name

Attributes

LocalizabilityAttribute

Examples

The following example sets the Name property in code, and then registers the name into the newly created NameScope by calling RegisterName. The technique illustrated here is a requirement for animating with storyboards, because storyboards require targeting by the Name, and cannot be targeted by object reference.

//  
// Create a Rectangle
//
Rectangle myRectangle = new Rectangle();
myRectangle.Width = 200;
myRectangle.Height = 200;
myRectangle.Name = "myRectangle";
this.RegisterName(myRectangle.Name, myRectangle);

'  
' Create a Rectangle
'
Dim myRectangle As New Rectangle()
myRectangle.Width = 200
myRectangle.Height = 200
myRectangle.Name = "myRectangle"
Me.RegisterName(myRectangle.Name, myRectangle)

Remarks

The most common usage of this property is to specify a XAML element name as an attribute in markup.

This property essentially provides a WPF framework-level convenience property to set the XAML x:Name Directive.

Names must be unique within a namescope. For more information, see WPF XAML Namescopes.

Getting a Name if you are creating elements in code is not common. If you have the appropriate reference in code already, you can just call methods and properties on the element reference and will not generally need the Name. An exception to this is if the Name string has some overloaded meaning, for instance if it is useful to display that name in UI. Setting a Name from code-behind if the original Name was set from markup is also not recommended, and changing the property after loading the XAML will not change the original object reference. The object references are created only when the underlying namescopes are explicitly created during parsing. You must specifically call RegisterName to make an effective change to the Name property of an already loaded element.

One notable case where setting Name from code is important is when registering names for elements that storyboards will run against, so that they can be referenced at run time. Before you can register a name, might also need to instantiate and assign a NameScope instance. See the Example section, or Storyboards Overview.

Setting Name from code has limited applications, but getting an element by Name is more common. One particular scenario is if your application supports a navigation model where pages reload into the application, and the run time code is not necessarily code-behind defined for that page. The utility method FindName, which is available from any FrameworkElement, can find any element by Name in the logical tree for that element, searching the tree recursively as necessary. Or you can use the FindLogicalNode static method of LogicalTreeHelper, which also takes a Name string as an argument.

Typically used root elements (Window, Page for example) implement the interface INameScope. Implementations of this interface are expected to enforce that names be unambiguous within their scope. The root elements that define this interface also define the namescope behavior boundaries for all the related APIs.

The Name property also serves as an identifier for other processes. For instance, the WPF automation model will use Name as the AutomationId for clients and providers.

The string values used for Name have some restrictions, as imposed by the underlying x:Name Directive defined by the XAML specification. Most notably, a Name must start with a letter or the underscore character (_), and must contain only letters, digits, or underscores. For more information, see WPF XAML Namescopes.

Name is one of the very few dependency properties that cannot be animated (IsAnimationProhibited is true in metadata), because the name itself is vital for targeting an animation. Data binding a Name is technically possible, but is an extremely uncommon scenario because a data-bound Name cannot serve the main intended purpose of the property: to provide an identifier connection point for code-behind.

Dependency Property Information

Identifier field	NameProperty
Metadata properties set to true	IsAnimationProhibited