Take the 2-minute tour ×  I've got a class called List_Field
that, as the name suggests, builds list input fields. These list
input fields allow users to select a single item per list.  I
want to be able to build list input fields that would allow
users to select multiple items per list, so I have the following
dilemma:  Should I do that through implementing a
multiple_choice_allowed property into the existing List_Field
property, or should I implement a Multiple_Choice_List_Field
subclass of the List_Field class?  What's the engineering
principle that I should follow when confronted with dilemmas
like this one?  share|improve this question .NET uses property
approach itself. –  atoMerz May 15 '11 at 13:07 in html, you got
your < select > single list and your < select multiple > list,
seems to have worked out ok :) –  Neil McGuigan Aug 11 '11 at
7:16 add comment  5 Answers  up vote 19 down vote accepted  Take
a look at the SOLID principles. They'll help you in your
designs. In particular, the single responsib