แก้ไข

แชร์ผ่าน


SourceChangedEventArgs Class

Definition

Provides data for the SourceChanged event, used for interoperation. This class cannot be inherited.

public ref class SourceChangedEventArgs sealed : System::Windows::RoutedEventArgs
public sealed class SourceChangedEventArgs : System.Windows.RoutedEventArgs
type SourceChangedEventArgs = class
    inherit RoutedEventArgs
Public NotInheritable Class SourceChangedEventArgs
Inherits RoutedEventArgs
Inheritance
SourceChangedEventArgs

Remarks

The SourceChanged event is a routed event where the event identifier is not publicly exposed. This is because this event plays a potentially critical part in interoperation and should not be allowed to be raised arbitrarily by any other source than the internal implementation of a known PresentationSource subclass (currently, the only such class is HwndSource). When implementing an interoperation solution, you can attach or remove handlers for the event (by calling AddSourceChangedHandler and RemoveSourceChangedHandler, respectively) but you cannot perform other operations normally available to routed events such as class handling, adding owners, or raising the event from an arbitrary element source.

This class overrides the RoutedEventArgs virtual method RoutedEventArgs.InvokeEventHandler, in order to return a type-specific handler when requested by the event system. This SourceChangedEventArgs override does not appear in the class members table in this SDK documentation because it is a protected member implemented by a sealed class.

Constructors

SourceChangedEventArgs(PresentationSource, PresentationSource, IInputElement, IInputElement)

Initializes a new instance of the SourceChangedEventArgs class, using supplied information for the old and new sources, the element that this change effects, and the previous reported parent of that element.

SourceChangedEventArgs(PresentationSource, PresentationSource)

Initializes a new instance of the SourceChangedEventArgs class, using supplied information for the old and new sources.

Properties

Element

Gets the element whose parent change causing the presentation source information to change.

Handled

Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route.

(Inherited from RoutedEventArgs)
NewSource

Gets the new source involved in this source change.

OldParent

Gets the previous parent of the element whose parent change causing the presentation source information to change.

OldSource

Gets the old source involved in this source change.

OriginalSource

Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class.

(Inherited from RoutedEventArgs)
RoutedEvent

Gets or sets the RoutedEvent associated with this RoutedEventArgs instance.

(Inherited from RoutedEventArgs)
Source

Gets or sets a reference to the object that raised the event.

(Inherited from RoutedEventArgs)

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
InvokeEventHandler(Delegate, Object)

When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation.

(Inherited from RoutedEventArgs)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnSetSource(Object)

When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes.

(Inherited from RoutedEventArgs)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also