DependencyPropertyChangedEventArgs Structure
Provides data for various property changed events. Typically these events report effective value changes in the value of a read-only dependency property. Another usage is as part of a PropertyChangedCallback implementation.
Assembly: WindowsBase (in WindowsBase.dll)
The DependencyPropertyChangedEventArgs type exposes the following members.
| Name | Description | |
|---|---|---|
![]() | DependencyPropertyChangedEventArgs | Initializes a new instance of the DependencyPropertyChangedEventArgs class. |
| Name | Description | |
|---|---|---|
![]() | Equals(DependencyPropertyChangedEventArgs) | Determines whether the provided DependencyPropertyChangedEventArgs is equivalent to the current DependencyPropertyChangedEventArgs. |
![]() | Equals(Object) | Determines whether the provided object is equivalent to the current DependencyPropertyChangedEventArgs. (Overrides ValueType::Equals(Object).) |
![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() | GetHashCode | Gets a hash code for this DependencyPropertyChangedEventArgs. (Overrides ValueType::GetHashCode().) |
![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() | ToString | Returns the fully qualified type name of this instance. (Inherited from ValueType.) |
| Name | Description | |
|---|---|---|
![]() ![]() | Equality | Determines whether two specified DependencyPropertyChangedEventArgs objects have the same value. |
![]() ![]() | Inequality | Determines whether two specified DependencyPropertyChangedEventArgs objects are different. |
The events that use the DependencyPropertyChangedEventArgs class for event data, and the DependencyPropertyChangedEventHandler method implementations for handlers, generally follow the naming pattern Is*Changed, and are generally implemented as common language runtime (CLR) events without RoutedEvent backing (they are not routed events). Some class handling methods that "handle" otherwise unexposed events that report a state change through a property change, such as ButtonBase::OnIsPressedChanged, also use the DependencyPropertyChangedEventArgs class for event data.
The scenario for PropertyChangedCallback is to use the arguments to report old and new values that come from the property system evaluation of the property. A callback that processes old and new values might choose special handling depending on these values, such as choosing to not respond to value changes that are deemed insignificant.
The following example uses the DependencyPropertyChangedEventArgs class in the context of a PropertyChangedCallback for a particular property of a custom class that also defines events. The callback takes the results of old and new values from the property system as communicated by DependencyPropertyChangedEventArgs, and repackages these into a different events arguments class RoutedPropertyChangedEventArgs<T>. The new arguments are then used as the data for a "ValueChanged" event defined by and raised by the custom class.
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
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
