WPF MVVM和行为 - 使用AssociatedObject.DataContext是一种很好的做法

Question

使用WPF行为时 - 使用为AssociatedObject.DataContext定义的ViewModel是一种很好的做法（MVVM方面）吗？就像行为中的这个事件处理程序一样：

    private void Plate_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        UserControl userControl = AssociatedObject as UserControl;
        Border borderParent = userControl.Parent as Border;
        PlateViewModel plateViewModel = userControl.DataContext as PlateViewModel;

        plateViewModel.ElementSelectedItem.Caption = "Selected Item";
    }