Question

If I have, say, a table of films which amongs other things has a int FilmTypeId field and a table of film types, with the id and a meaningful description along the lines of:

• 1 – horror
• 2 – comedy
• …

Whats the best way of using that information in a C# class?

currently I would have them as Constants in a helper class (unsuprisingly air code):

public class FilmHelper {     public const int HorrorFilmType = 1;     public const int ComedyFilmType = 2;     ... } 

but this doesn’t seem that maintainable. But I would like to avoid a database call everytime I came to use the constant or an additional db call everytime I used either the helper or the main entity.

Answer 1

Is the list of types fixed or does it change?

If fixed, I would encapsulate it in an enum:

public enum FilmType {    Horror = 1,    Comedy = 2 } 

Then just cast. You can use attributes (and a few lines of bespoke code) to store an extra description per enum item.

If the list changes I would probably read it once early on in the app, and cache the list in a lookup somewhere (perhaps static, perhaps in a specific cache). Then just do the lookups from the cached copy.

You can take this further by adding properties that change between the two representations.