StackPanel PreviewTextInput and PreviewKeyDown : Key Event « Windows Presentation Foundation « VB.Net Tutorial

1. VB.Net Tutorial
2. Windows Presentation Foundation
3. Key Event

<Window x:Class="RoutedEvents.OnlyNumbers"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Only Numbers" Height="300" Width="300">
    <StackPanel Margin="5" PreviewTextInput="pnl_PreviewTextInput" PreviewKeyDown="pnl_PreviewKeyDown">
        <TextBox Margin="3" AcceptsTab="False"></TextBox>
        <TextBox Margin="3"></TextBox>
        <TextBox Margin="3"></TextBox>
    </StackPanel>
    
</Window>
//File:Window.xaml.vb

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Data
Imports System.Windows.Documents
Imports System.Windows.Input
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Imports System.Windows.Shapes

Namespace RoutedEvents
  Public Partial Class OnlyNumbers
    Inherits System.Windows.Window
    Public Sub New()
      InitializeComponent()
    End Sub
    Private Sub pnl_PreviewTextInput(sender As Object, e As TextCompositionEventArgs)
      Dim val As Short
      If Not Int16.TryParse(e.Text, val) Then
        e.Handled = True
      End If
    End Sub

    Private Sub pnl_PreviewKeyDown(sender As Object, e As KeyEventArgs)
      If e.Key = Key.Space Then
        e.Handled = True
      End If
    End Sub
  End Class
End Namespace

16.90.Key Event
	16.90.1.	Creating a KeyBinding between the Open command and Ctrl-R
	16.90.2.	Command Handler Key Binding
	16.90.3.	Use Keyboard.Focus to set the focus to a Text Field
	16.90.4.	Provide Quick Keyboard Access to Buttons
	16.90.5.	Reading keyboard modifiers
	16.90.6.	Reading individual key state with Keyboard.IsKeyDown
	16.90.7.	Use InputBinding to bind Application commends to Key events
	16.90.8.	Suppress Keyboard and Mouse Events
	16.90.9.	Query Left / Right control key
	16.90.10.	Is Key.CapsLock Toggled
	16.90.11.	Keyboard.IsKeyToggled
	16.90.12.	Query Number lock key
	16.90.13.	Use KeyBinding to bind Key event to TextBox.InputBindings
	16.90.14.	Custom Command by KeyGesture and RoutedUICommand
	16.90.15.	TextBox PreviewKeyDown, PreviewKeyUp, PreviewTextInput, KeyDown, KeyUp and TextChanged events
	16.90.16.	StackPanel PreviewTextInput and PreviewKeyDown
	16.90.17.	If input is not a number do not handle the key event
	16.90.18.	RoutedEvents: Tunneled Key Press
	16.90.19.	On Key Down Handler