WPF(二)路由事件1.冒泡路由事件

　　WPF中的路由事件是具有更强传播能力的事件,它们可以在元素树中向上冒泡和向下隧道传播,并且沿着传播路径被事件处理程序处理。

下面的例子演示了事件冒泡的过程。

<Window x:Class="Prj05_1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="BubbledLabelClick" Height="359" Width="329">
    <Grid Margin="3" MouseUp="SomethingClicked">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
        </Grid.RowDefinitions>
        <Label Margin="5" Grid.Row="0" HorizontalAlignment="Left" Background="AliceBlue" BorderBrush="Black" BorderThickness="1"
               MouseUp="SomethingClicked">
            <StackPanel MouseUp="SomethingClicked">
                <TextBlock Margin="3" MouseUp="SomethingClicked">Image and text label</TextBlock>
                <Image Source="lianjie.png" Stretch="None" MouseUp="SomethingClicked"/>
                <TextBlock Margin="3" MouseUp="SomethingClicked">Courtesy of the StackPanel</TextBlock>
            </StackPanel>
        </Label>
        <ListBox Grid.Row="1" Margin="5" Name="lstMessage"></ListBox>
        <CheckBox Grid.Row="2" Margin="5" Name="chkHandle">Handle first event</CheckBox>
        <Button Grid.Row="3" Margin="5" Padding="3" HorizontalAlignment="Right" Name="cmdCenter"
                Click="cmdClear_Click">Clear List</Button>
    </Grid>
</Window>

事件代码:

  private void SomethingClicked(object sender, MouseButtonEventArgs e)
        {
            eventCounter++;
            string message = "#" + eventCounter.ToString() + ":\r\n" +
                " Sender:" + sender.ToString() + "\r\n" +
                " Source: " + e.Source + "\r\n" +
                " Original Source:" + e.OriginalSource;
            lstMessage.Items.Add(message);
            e.Handled = (bool)chkHandle.IsChecked;
        }

private void cmdClear_Click(object sender, RoutedEventArgs e)
        {
            lstMessage.Items.Clear();
        }

程序运行后的效果:

当点击Image时可以看到事件的响应过程是从最底层开始的。