WPF EventTrigger example

    xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"

    <ComboBox x:Name="ComboEncoding"
              SelectedIndex="{Binding SelectedIndex}"
              MinWidth="75">
        <i:Interaction.Triggers>
            <i:EventTrigger EventName="DropDownClosed">
                <i:InvokeCommandAction Command="{Binding EncodingChangedCommand}"></i:InvokeCommandAction>
            </i:EventTrigger>
        </i:Interaction.Triggers>
        <ComboBoxItem>UTF-8</ComboBoxItem>
        <ComboBoxItem>ISO-8859-1</ComboBoxItem>
    </ComboBox>

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