Binding.Path Property

Definition

Namespace:

System.Windows.Data

Assembly:

PresentationFramework.dll

Gets or sets the path to the binding source property.

public:
 property System::Windows::PropertyPath ^ Path { System::Windows::PropertyPath ^ get(); void set(System::Windows::PropertyPath ^ value); };

public System.Windows.PropertyPath Path { get; set; }

member this.Path : System.Windows.PropertyPath with get, set

Public Property Path As PropertyPath

Property Value

PropertyPath

The path to the binding source. The default is null.

Examples

The following example shows a style trigger that creates a ToolTip that reports a validation error message. The value of the setter binds to the error content of the current TextBox (the TextBox using the style) using the RelativeSource property. For more information on this example, see How to: Implement Binding Validation.

<Style x:Key="textBoxInError" TargetType="{x:Type TextBox}">
  <Style.Triggers>
    <Trigger Property="Validation.HasError" Value="true">
      <Setter Property="ToolTip"
        Value="{Binding RelativeSource={x:Static RelativeSource.Self},
                        Path=(Validation.Errors)/ErrorContent}"/>
    </Trigger>
  </Style.Triggers>
</Style>

Remarks

Each binding typically has these four components: a binding target object, a target property, a binding source, and a path to the value in the binding source to use. For more information about these data binding concepts, see Data Binding Overview.

Use the Path property to specify the source value you want to bind to:

• In the simplest case, the Path property value is the name of the property of the source object to use for the binding, such as Path=PropertyName.

• Subproperties of a property can be specified by a syntax similar to that used in C#. For instance, the clause Path=ShoppingCart.Order sets the binding to the subproperty Order of the object or property ShoppingCart.

• To bind to an attached property, place parentheses around the attached property. For example, to bind to the attached property DockPanel.Dock, the syntax is Path=(DockPanel.Dock).

• Indexers of a property can be specified within square brackets following the property name where the indexer is applied. For instance, the clause Path=ShoppingCart[0] sets the binding to the index that corresponds to how your property's internal indexing handles the literal string "0". Multiple indexers are also supported.

• Indexers and subproperties can be mixed in a Path clause; for example, Path=ShoppingCart.ShippingInfo[MailingAddress,Street].

• Inside indexers you can have multiple indexer parameters separated by commas (,). The type of each parameter can be specified with parentheses. For example, you can have Path="[(sys:Int32)42,(sys:Int32)24]", where sys is mapped to the System namespace.

• When the source is a collection view, the current item can be specified with a slash (/). For example, the clause Path=/ sets the binding to the current item in the view. When the source is a collection, this syntax specifies the current item of the default collection view.

• Property names and slashes can be combined to traverse properties that are collections. For example, Path=/Offices/ManagerName specifies the current item of the source collection, which contains an Offices property that is also a collection. Its current item is an object that contains a ManagerName property.

• Optionally, a period (.) path can be used to bind to the current source. For example, Text="{Binding}" is equivalent to Text="{Binding Path=.}".

For information about path syntax, see Binding Declarations Overview or PropertyPath XAML Syntax.

For XML bindings, see the XPath property.

To bind to an entire object, you do not need to specify the Path property. For more information, see "Specifying the Path to the Value" in Data Binding Overview.