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UIElement.MouseLeave Event

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Occurs when the mouse (or the stylus) leaves the bounding area of a UIElement.

Namespace:  System.Windows
Assembly:  System.Windows (in System.Windows.dll)

Syntax

'Declaration
Public Event MouseLeave As MouseEventHandler
public event MouseEventHandler MouseLeave
<uiElement MouseLeave="eventhandler"/>

Remarks

Use a handler based on MouseEventHandler to handle this event. For more information on how to handle mouse events, see Mouse Support.

The MouseLeave event can be defined for any UIElement-derived class, such as Canvas, TextBlock, or Rectangle.

The MouseLeave event is raised in response to the mouse (or the stylus) leaving the object's bounding area.

You can define multiple MouseLeave events for objects in XAML content. However, if a child object and its parent object both define a MouseLeave event, the parent object's MouseLeave event occurs before the child object's MouseLeave event. This is not a case of a bubbling event; it indicates only that the mouse (or the stylus) has entered both objects, potentially at different times depending on the object layout and composition of the visual tree.

Unlike the MouseEnter event, the MouseLeave event does not provide the mouse (or the stylus) position in event data, because the position of the mouse pointer relative to the object is unknown when it is out of bounds. Because it is always nulla null reference (Nothing in Visual Basic), you generally should not use the event data from your MouseLeave event handler, although you may still be interested in the sender parameter.

MouseLeave events do not route, they can only be handled on the element that raises them. For details, see the "MouseEnter and MouseLeave Events" section of Mouse Support.

MouseLeave and OnMouseLeave

Controls that inherit MouseLeave can provide handling for the event that acts as handler for all instances, by overriding the OnMouseLeave method. OnMouseLeave can be useful either for setting visual state, or for public or internal state properties. For instance, Slider implements OnMouseLeave in order to check the Thumb element's value for IsDragging (which cancels a particular behavior mode), and also to set visual state. For more information, see OnMouseLeave.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

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

Platforms

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