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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: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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