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InvokeEventHandler Method
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SelectionChangedEventArgs.InvokeEventHandler Method

Performs the proper type casting to call the type-safe SelectionChangedEventHandler delegate for the SelectionChanged event.

Namespace:  System.Windows.Controls
Assembly:  PresentationFramework (in PresentationFramework.dll)

protected override void InvokeEventHandler(
	Delegate genericHandler,
	Object genericTarget
)

Parameters

genericHandler
Type: System.Delegate

The handler to invoke.

genericTarget
Type: System.Object

The current object along the event's route.

The following example creates a ListBox and subscribes to the SelectionChanged event. It uses the SelectionChangedEventArgs to find the selected item in the ListBox.

      <WrapPanel Width="500" Orientation="Horizontal" Name="rectanglesPanel">
        <WrapPanel.Resources>
          <Style TargetType="Rectangle">
            <Setter Property="Height" Value="20"/>
            <Setter Property="Width" Value="20"/>
            <Setter Property="Margin" Value="5"/>
          </Style>
        </WrapPanel.Resources>
      </WrapPanel>

      <ListBox Name="myListBox" HorizontalAlignment="Left" SelectionMode="Extended" 
            Width="265" Height="55" Background="HoneyDew" SelectionChanged="myListBox_SelectionChanged"
            ItemsSource="{Binding Source={StaticResource Colors}}" IsSynchronizedWithCurrentItem="true">
      </ListBox>
void myListBox_SelectionChanged(object sender, SelectionChangedEventArgs args)
{

    BrushConverter converter = new BrushConverter();

    // Show Rectangles that are the selected colors. 
    foreach (string color in args.AddedItems)
    {
        if (GetRectangle(color) == null)
        {
            Rectangle aRect = new Rectangle();
            aRect.Fill = (Brush) converter.ConvertFrom(color);
            aRect.Tag = color;
            rectanglesPanel.Children.Add(aRect);
        }

    }

    // Remove the Rectangles that are the unselected colors. 
    foreach (string color in args.RemovedItems)
    {
        FrameworkElement removedItem = GetRectangle(color);
        if (removedItem != null)
        {
            rectanglesPanel.Children.Remove(removedItem);
        }
    }
}

FrameworkElement GetRectangle(string color)
{
    foreach (FrameworkElement rect in rectanglesPanel.Children)
    {
        if (rect.Tag.ToString() == color)
            return rect;
    }

    return null;
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
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