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TextBox.OnKeyDown Method

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

Called when KeyDown event occurs.

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 OnKeyDown method is called before any event handler for the KeyDown event is called. This method allows derived classes to handle the KeyDown event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

This implementation marks the KeyDown event as handled by setting the Handled property of the event data to true.

The TextBox control handles navigation and edit keys when it performs an action, but it does not handle keys related to text input. Derived classes can block text input by handling keys related to text input.

Notes to Inheritors

If you override the OnKeyDown method, you can prevent registered delegates from receiving events by setting Handled to true. For more information about routed events and the Handled property, see Events Overview for Silverlight.

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.