I know it is possible to do this by working with ICommand, but since this is the only place in my whole project where this is needed, I am asking myself, if there is maybe a bet
You could use the Click eventhandler of the Button. Then you don't need any Commands.
private void bt_Delete_Click(object sender, RoutedEventArgs e)
{
var btn = sender as Button;
YourClass dc = btn.DataContext as YourClass;
dc.IsToDelete = true;
}
I don't really like this solution, but I think, it would work.