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ListBox.OnKeyDown Method

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

Provides handling for the KeyDown event that occurs when a key is pressed while the control has focus.

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

Syntax

'Declaration
Protected Overrides Sub OnKeyDown ( _
    e As KeyEventArgs _
)

protected override void OnKeyDown(
    KeyEventArgs e
)

Parameters

Remarks

The following table lists keys that will cause the KeyDown event to be marked as handled. It also describes how the ListBox handles the key.

Key

Action

Ctrl and Space

If the list item with focus is currently selected, it is deselected. If it is not selected, it is set as the selected item.

Home

Sets the first list item is set as the selected item.

End

Sets the last list item is set as the selected item.

PageUp

Sets the previous list item as the selected item.

PageDown

Sets the next list item as the selected item.

Left

If the ListBox is oriented vertically, scrolls the list to the left. If the ListBox is oriented horizontally, sets the previous item in the list as the selected item.

Up

If the ListBox is oriented horizontally, scrolls the list to the list. If the ListBox is oriented vertically, sets the previous item in the list as the selected item.

Right

If the ListBox is oriented vertically, scrolls the list to the right. If the ListBox is oriented horizontally, sets the next item in the list as the selected item.

Down

If the ListBox is oriented horizontally, scrolls the list down. If the ListBox is oriented vertically, sets the next item in the list as the selected item.

The OnKeyDown method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnKeyDown in a derived class, be sure to call the base class’s OnKeyDown method so that registered delegates receive the event.

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.