On Key Down Handler : Key Event « Windows Presentation Foundation « C# / CSharp Tutorial

1. C# / CSharp Tutorial
2. Windows Presentation Foundation
3. Key Event

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="KeyDown Sample" Height="400" Width="500">
  <StackPanel>
    <TextBlock Width="300" Height="20">
      Type some text into the TextBox and press the Enter key.
    </TextBlock>
    <TextBox Width="300" Height="30" Name="textBox1"
             KeyDown="OnKeyDownHandler"/>
    <TextBlock Width="300" Height="100" Name="textBlock1"/>
  </StackPanel>
</Window>

//File:Window.xaml.cs

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;


namespace WpfApplication1
{
    public partial class Window1 : Window
    {

        public Window1()
        {
            InitializeComponent();
        }
        private void OnKeyDownHandler(object sender, KeyEventArgs e)
        {
            if (e.Key == Key.Return)
            {
                textBlock1.Text = "You Entered: " + textBox1.Text;
            }
        }
    }
}

24.122.Key Event
	24.122.1.	Query Left / Right control key
	24.122.2.	Query Left / Right Shift key
	24.122.3.	Is Key.CapsLock Toggled
	24.122.4.	Keyboard.IsKeyToggled
	24.122.5.	Query Number lock key
	24.122.6.	Use Keyboard.Focus to set the focus to a Text Field
	24.122.7.	Programmatically Extract an Element's Style with DefaultStyleKeyProperty
	24.122.8.	Provide Quick Keyboard Access to Buttons
	24.122.9.	Reading keyboard modifiers
	24.122.10.	Reading individual key state with Keyboard.IsKeyDown
	24.122.11.	Suppress Keyboard and Mouse Events
	24.122.12.	Use KeyBinding to bind Key event to TextBox.InputBindings
	24.122.13.	StackPanel PreviewTextInput and PreviewKeyDown
	24.122.14.	If input is not a number do not handle the key event
	24.122.15.	On Key Down Handler
	24.122.16.	Check if it is a key down action
	24.122.17.	Check if it is a key up action
	24.122.18.	Record Key strokes
	24.122.19.	Override OnTextInput method to get the input from key board
	24.122.20.	TextBox key pressed action listener, and set caret index for TextBox
	24.122.21.	override key down method to listen to key down event
	24.122.22.	Check key code for Key.Up and Key.Down