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DependencyPropertyChangedEventArgs Structure

Provides data for a PropertyChangedCallback implementation.

Namespace:  System.Windows
Assembly:  System.Windows (in System.Windows.dll)
public struct DependencyPropertyChangedEventArgs

The DependencyPropertyChangedEventArgs type exposes the following members.

  Name Description
Public property Supported by Silverlight for Windows Phone NewValue Gets the value of the property after the change.
Public property Supported by Silverlight for Windows Phone OldValue Gets the value of the property before the change.
Public property Supported by Silverlight for Windows Phone Property Gets the identifier for the dependency property where the value change occurred.
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  Name Description
Public method Supported by Silverlight for Windows Phone Equals Indicates whether this instance and a specified object are equal. (Inherited from ValueType.)
Protected method Supported by Silverlight for Windows Phone Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public method Supported by Silverlight for Windows Phone GetHashCode Returns the hash code for this instance. (Inherited from ValueType.)
Public method Supported by Silverlight for Windows Phone GetType Gets the Type of the current instance. (Inherited from Object.)
Protected method Supported by Silverlight for Windows Phone MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method Supported by Silverlight for Windows Phone ToString Returns the fully qualified type name of this instance. (Inherited from ValueType.)
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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. Some example scenarios include:

  • Choosing to not respond to value changes that are deemed insignificant.

  • Rejecting property changes that fail a property-specific or circumstantial validation.

  • Checking/setting other property values that exist in a dependency relationship with the property that changed.

  • Raising an event from the class.

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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