[WPF] ComboBox Command Binding 하기

xaml 단에 아래 처럼 선언하고

xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"

<ComboBox ItemsSource="{Binding Datas}" SelectedItem="{Binding SelectedData}">
    <i:Interaction.Triggers>
        <i:EventTrigger EventName="SelectionChanged">
            <i:InvokeCommandAction Command="{Binding DataCommand}" />
        </i:EventTrigger>
    </i:Interaction.Triggers>
</ComboBox>