Store the variable in the application and get it back


   
  

<Window x:Class="BookApp.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="BookApp" Height="300" Width="300">
    <Grid>
      <Button Click="MyClickEvent" 
        VerticalAlignment="Top" 
        HorizontalAlignment="Stretch" 
        Grid.Column="0" 
        Grid.ColumnSpan="1" 
        Grid.Row="0" 
        Grid.RowSpan="1"
        Name="btnGo">Go</Button>
    </Grid>
</Window>

//File:Window.xaml.cs
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;


namespace BookApp
{
    public partial class Window1 : System.Windows.Window
    {
        public Window1()
        {
            InitializeComponent();

            Book x = new Book();
            x.author = "Author";
            x.title = "Title";
            x.price = (decimal)9.99;

            
            Application.Current.Properties["Book"] = x;
        }

        private void MyClickEvent(object sender, RoutedEventArgs e)
        {
            Book y = (Book)Application.Current.Properties["Book"];

            MessageBox.Show(y.title, y.author, MessageBoxButton.OK,MessageBoxImage.Hand);
        }

    }

    public class Book
    {
        public decimal price;
        public string title;
        public string author;
    }

}

   
    
     


Application.Current.Windows stores all windows you created


   
  


<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="AppWindowsSample" Height="200" Width="300" 
    xmlns:my="clr-namespace:System;assembly=mscorlib">
  <StackPanel>
    <Menu Name="menu1" >
      <MenuItem Header="Window" x:Name="windowMenu">
        <MenuItem Header="SubmenuOpened event" />
      </MenuItem>
    </Menu>
    <Button Margin="10" Name="newWindowButton" Height="23" VerticalAlignment="Top">New Window</Button>
    <StatusBar Grid.Row="2" Name="statusBar1" >
      <TextBlock x:Name="statusText">Status</TextBlock>
    </StatusBar>
    <Button Height="23" Margin="10" Name="shutdownButton" VerticalAlignment="Top" >Shutdown</Button>
  </StackPanel>
</Window>
//File:Window.xaml.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Windows.Controls.Primitives;
using System.Diagnostics;
using System.ComponentModel;


namespace WpfApplication1 {
  public partial class Window1 : System.Windows.Window {

    public Window1() {
      InitializeComponent();

      DataContext = Application.Current.Windows;
      statusText.Text = Application.Current.ShutdownMode.ToString();

      newWindowButton.Click += new RoutedEventHandler(newWindowButton_Click);
      shutdownButton.Click += new RoutedEventHandler(shutdownButton_Click);
      windowMenu.SubmenuOpened += new RoutedEventHandler(windowMenu_SubmenuOpened);
      Closing += Window1_Closing;
    }

    public void windowMenu_SubmenuOpened(object sender, RoutedEventArgs e) {
      windowMenu.Items.Clear();
      foreach( Window window in Application.Current.Windows ) {
        MenuItem item = new MenuItem();
        item.Header = window.Title;
        item.Click += windowMenuItem_Click;
        item.Tag = window;
        item.IsChecked = window.IsActive;
        windowMenu.Items.Add(item);
      }
    }

    public void windowMenuItem_Click(object sender, RoutedEventArgs e) {
      Window window = (Window)((MenuItem)sender).Tag;
      window.Activate();
    }

    public void newWindowButton_Click(object sender, RoutedEventArgs e) {
      Window window = new Window();
      window.Title = "Window " + DateTime.Now;
      window.Width = 200;
      window.Height = 100;
      window.Show();
      statusText.Text = Application.Current.ShutdownMode.ToString();
    }

    void shutdownButton_Click(object sender, RoutedEventArgs e) {
      Application.Current.Shutdown();
    }

    void Window1_Closing(object sender, CancelEventArgs e) {
      if( MessageBox.Show("Do you really want to shut down?", "Shutting Down", MessageBoxButton.YesNo) == MessageBoxResult.No ) {
        e.Cancel = true;
      }
    }


  }
}

   
    
     


Application.Current.ShutdownMode


   
  


<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="AppWindowsSample" Height="200" Width="300" 
    xmlns:my="clr-namespace:System;assembly=mscorlib">
  <StackPanel>
    <Menu Name="menu1" >
      <MenuItem Header="Window" x:Name="windowMenu">
        <MenuItem Header="SubmenuOpened event" />
      </MenuItem>
    </Menu>
    <Button Margin="10" Name="newWindowButton" Height="23" VerticalAlignment="Top">New Window</Button>
    <StatusBar Grid.Row="2" Name="statusBar1" >
      <TextBlock x:Name="statusText">Status</TextBlock>
    </StatusBar>
    <Button Height="23" Margin="10" Name="shutdownButton" VerticalAlignment="Top" >Shutdown</Button>
  </StackPanel>
</Window>
//File:Window.xaml.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Windows.Controls.Primitives;
using System.Diagnostics;
using System.ComponentModel;


namespace WpfApplication1 {
  public partial class Window1 : System.Windows.Window {

    public Window1() {
      InitializeComponent();

      DataContext = Application.Current.Windows;
      statusText.Text = Application.Current.ShutdownMode.ToString();

      newWindowButton.Click += new RoutedEventHandler(newWindowButton_Click);
      shutdownButton.Click += new RoutedEventHandler(shutdownButton_Click);
      windowMenu.SubmenuOpened += new RoutedEventHandler(windowMenu_SubmenuOpened);
      Closing += Window1_Closing;
    }

    public void windowMenu_SubmenuOpened(object sender, RoutedEventArgs e) {
      windowMenu.Items.Clear();
      foreach( Window window in Application.Current.Windows ) {
        MenuItem item = new MenuItem();
        item.Header = window.Title;
        item.Click += windowMenuItem_Click;
        item.Tag = window;
        item.IsChecked = window.IsActive;
        windowMenu.Items.Add(item);
      }
    }

    public void windowMenuItem_Click(object sender, RoutedEventArgs e) {
      Window window = (Window)((MenuItem)sender).Tag;
      window.Activate();
    }

    public void newWindowButton_Click(object sender, RoutedEventArgs e) {
      Window window = new Window();
      window.Title = "Window " + DateTime.Now;
      window.Width = 200;
      window.Height = 100;
      window.Show();
      statusText.Text = Application.Current.ShutdownMode.ToString();
    }

    void shutdownButton_Click(object sender, RoutedEventArgs e) {
      Application.Current.Shutdown();
    }

    void Window1_Closing(object sender, CancelEventArgs e) {
      if( MessageBox.Show("Do you really want to shut down?", "Shutting Down", MessageBoxButton.YesNo) == MessageBoxResult.No ) {
        e.Cancel = true;
      }
    }


  }
}

   
    
     


Implement Application.DoEvents in WPF






//File:Window.xaml.cs

using System.Windows;
using System.Windows.Threading;

namespace WpfApplication1
{
public partial class Window1 : Window
{
private delegate void EmptyDelegate();
public Window1()
{
InitializeComponent();
}

private void btnWithout_Click(object sender, RoutedEventArgs e)
{
LoadNumbers(false);
}

private void btnWith_Click(object sender, RoutedEventArgs e)
{
LoadNumbers(true);
}

private void LoadNumbers(bool callDoEvents)
{
listBox.Items.Clear();

btnWithout.IsEnabled = false;
btnWith.IsEnabled = false;

for(int i = 1; i <= 10000; i++) { listBox.Items.Add("Number " + i.ToString()); if(callDoEvents){ DoEvents(); } } btnWithout.IsEnabled = true; btnWith.IsEnabled = true; } public static void DoEvents() { Dispatcher.CurrentDispatcher.Invoke(DispatcherPriority.Background,new EmptyDelegate(delegate{})); } } } [/csharp]

Throw Application event from button click event handler


   
  

<Window x:Class="PreventSessionEnd.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="PreventSessionEnd" Height="300" Width="300"
    >
    <Grid Margin="5">
      <Button Click="cmdException_Click">Throw an Unhandled Exception</Button>
    </Grid>
</Window>


//File:Window.xaml.cs
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;


namespace PreventSessionEnd
{

    public partial class Window1 : Window
    {

        public Window1()
        {
            InitializeComponent();
        }

        private void cmdException_Click(object sender, RoutedEventArgs e)
        {
            throw new ApplicationException("You clicked a bad button.");                
        }
    }
}

   
    
     


Animation with Discrete Key Frames


   
     

<Canvas xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
  <Image Source="c:image.png">
    <Image.Triggers>
      <EventTrigger RoutedEvent="Image.Loaded">
        <EventTrigger.Actions>
          <BeginStoryboard>
            <Storyboard>
              <DoubleAnimation Storyboard.TargetProperty="(Canvas.Left)" From="0" To="500" Duration="0:0:3"/>
              <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(Canvas.Top)" Duration="0:0:3">
                <DiscreteDoubleKeyFrame Value="0" KeyTime="0:0:0"/>
                <DiscreteDoubleKeyFrame Value="200" KeyTime="0:0:1"/>
                <DiscreteDoubleKeyFrame Value="0" KeyTime="0:0:2"/>
              </DoubleAnimationUsingKeyFrames>
            </Storyboard>
          </BeginStoryboard>
        </EventTrigger.Actions>
      </EventTrigger>
    </Image.Triggers>
  </Image>
</Canvas>






     


Animation with Mixed Key Frames.xaml


   
     
<Canvas xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
  <Image Source="c:image.png">
    <Image.Triggers>
      <EventTrigger RoutedEvent="Image.Loaded">
        <EventTrigger.Actions>
          <BeginStoryboard>
            <Storyboard>
              <DoubleAnimation Storyboard.TargetProperty="(Canvas.Left)" From="0" To="500" Duration="0:0:3"/>
              <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(Canvas.Top)" Duration="0:0:3">
                  <DiscreteDoubleKeyFrame Value="0" KeyTime="0:0:0"/>
                  <LinearDoubleKeyFrame Value="200" KeyTime="0:0:1"/>
                  <SplineDoubleKeyFrame KeySpline="0,1,1,0" Value="200" KeyTime="0:0:3"/>
              </DoubleAnimationUsingKeyFrames>
            </Storyboard>
          </BeginStoryboard>
        </EventTrigger.Actions>
      </EventTrigger>
    </Image.Triggers>
  </Image>
</Canvas>