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FrameworkElement.DataContext Property

Definition

Gets or sets the data context for an element when it participates in data binding.

public:
 property System::Object ^ DataContext { System::Object ^ get(); void set(System::Object ^ value); };
[System.Windows.Localizability(System.Windows.LocalizationCategory.NeverLocalize)]
public object DataContext { get; set; }
[<System.Windows.Localizability(System.Windows.LocalizationCategory.NeverLocalize)>]
member this.DataContext : obj with get, set
Public Property DataContext As Object

Property Value

The object to use as data context.

Attributes

Examples

The following example illustrates how a data context acts on a binding and provides the information that defines the specific values of bound properties.

<Window.Resources>
  <src:LeagueList x:Key="MyList" />
</Window.Resources>
<DockPanel DataContext="{Binding Source={StaticResource MyList}}">

Remarks

Data context is a concept that allows elements to inherit information from their parent elements about the data source that is used for binding, as well as other characteristics of the binding, such as the path.

Data context can be set directly to a .NET object, with the bindings evaluating to properties of that object. Alternatively, you can set the data context to a DataSourceProvider object.

This dependency property inherits property values. If there are child elements without other values for DataContext established through local values or styles, then the property system will set the value to be the DataContext value of the nearest parent element with this value assigned.

Alternatively, you can use one of the following properties of the Binding class to specify the binding source explicitly:

- <xref:System.Windows.Data.Binding.ElementName%2A>.
- <xref:System.Windows.Data.Binding.Source%2A>.
- <xref:System.Windows.Data.Binding.RelativeSource%2A>. 

For more information, see How to: Specify the Binding Source.

In XAML, DataContext is most typically set as a Binding declaration. You can use either property element syntax or attribute syntax. Attribute syntax is shown in the example on this page. You can also use code to set DataContext.

DataContext is a bindable property to facilitate scenarios where one context might be bound to another. However, if you bind to DataContext, be careful to not create circular binding references (do not bind a DataContext to itself, which it is possible to do because of the property value inheritance nature of the DataContext property).

XAML Property Element Usage

<object>  
  <object.DataContext>  
    <dataContextObject />  
  </object.DataContext>  
</object>  

XAML Attribute Usage

<object DataContext="bindingUsage"/>  

-or-

<object DataContext="{resourceExtension contextResourceKey}"/>  

XAML Values

dataContextObject
A directly embedded object that serves as data context for any bindings within the parent element. Typically, this object is a Binding or another BindingBase derived class. Alternatively, raw data of any object type intended for binding may be placed here, with the actual bindings defined later.

bindingUsage
A binding usage that evaluates to an appropriate data context. For details, see Binding Markup Extension.

resourceExtension
One of the following: StaticResource or DynamicResource. This usage is used when referring to raw data defined as an object in resources. See XAML Resources.

contextResourceKey
The key identifier for the object being requested from within a ResourceDictionary.

Dependency Property Information

Identifier field DataContextProperty
Metadata properties set to true Inherits

Applies to