Naming Conventions Regarding View Models to Avoid Long Names

Question

I am creating view models for each screen in my ASP.NET MVC application. I put all of the logic for creating a view model in a builder class. Usually, there is special logic for converting the data objects into view models, including aggregating, filtering, and sorting. Each builder is passed a dependency set, which is an object containing properties for each dependency (repositories, other builders, etc.).

The problem is that my names are getting really long. A dependency set will usually have a name composed this way:

view-model-name+Builder+DependencySet

View models usually have names composed of where you are currently and the children. For instance, my system has categorized provider definitions. So, in order to show the provider definitions under a category, I have a view model called:

CategoryProviderDefinitionListViewModel

It will look something like this:

public sealed class CategoryProviderDefinitionListViewModel
{
    public long CategoryId { get; set; }
    public string CategoryName { get; set; }
    public ProviderDefinitionViewModel[] ProviderDefinitions { get; set; }
}

So, my builder is called

CategoryProviderDefinitionListViewModelBuilder

So, my dependency set is called

CategoryProviderDefinitionListViewModelBuilderDependencySet

That barely fits across the screen. My poor fingers are tired. Furthermore, some screens almost show the same data, so their view model names are almost the same. When I am looking through my folder, it becomes really hard to find the specific view model classes I am looking for.

Ideally, I could group my view model classes together, associating them with the view(s) where they are used. It would be nice to avoid collisions and to make names as short as possible, while keeping them meaningful. Has anyone found a naming convention/folder organization that works well in this scenario?

score 10 · Accepted Answer · answered Mar 26 '12 at 05:47

I've been using the "ViewModel" suffix consistently for quite a while and to be honest, sometimes I find it redundant. I think just grouping all these classes in a different namespace should be sufficient.

My understanding is that this convention has been adopted to avoid collision between domain model and view model classes (eg Product vs ProductViewModel). However, since your view models are named after the screens, it is very unlikely that you would have a class with the same name in your domain model. In fact, it should be really questionable why you have such a class in your domain model! :)

So, if you name your view model something like ViewProduct (to allow the user to view/edit a product), you don't need to call it ViewProductViewModel. See where I'm going?

Consequently, your Builder class could simply be called ViewProductBuilder instead of ViewProductViewModelBuilder.

Regarding your dependency set, I'm not sure what is your rationale behind this. But to me it looks unnecessary. If your builder has dependencies to other objects, you'll need to inject dependencies in the constructor of builder, instead of encapsulating them into another class (DependencySet) and then passing them around.

If you find your builder dependent on too may things and this is what you are trying to hide behind DependencySet, then it could be the indication of a design smell somewhere else. If classes and their dependencies are designed in a proper object-oriented fashion, behavior should be distributed very nicely between various classes and no class should have dependency on too many other things. So, hiding those N dependencies under 1 class (DependencySet) is merely treating the symptoms not the problem itself.

Hope this help :)

score 3 · Answer 2 · answered May 12 '12 at 16:05

3

I prefer post-fixing my ViewModel names with "DTO". (Where DTO stands for Data Transfer Object, ie. an object that does nothing but contain information)

This is not only to avoid long names. But it also makes me able to use the same names like User, but it will be called UserDTO, indicating to me that I am working with an object that is part of my ViewModel, and thus avoid naming collisions.

answered May 12 '12 at 16:05

1

a [DTO is a different thing though](http://stackoverflow.com/questions/1051182/what-is-data-transfer-object), for a start, it's possible to have a DTO **and** view models in the same solution. – Liam Mar 06 '17 at 11:25
That's true. And if that situation arose, I would probably also opt for a different naming convention. But good point. – Mar 07 '17 at 19:42

score 1 · Answer 3 · answered Jan 15 '13 at 01:50

I tend to agree with Mosh.

The ViewModel suffix becomes redundant the majority of the time and while sometimes you might have matching class names, it is quite easy to manage as they are confined to your ViewModel namespace. I also find that using the odd namespace alias hurts my brain less than suffixing my class names across the board.

Of course in your presenter/controller you may have naming collisions, but that could be a sign that you need to name your Views more appropriately, e.g. not User but ViewUser/EditUser.

For search results and lists I find it is best to break out something such as IEnumerable instead of IEnumerable. The latter often means you end up with a User view model class that becomes a dumping ground for all User properties that may or may not be needed across the project. This is one of the big things to watch out for and if you find yourself with a class like this, you've gone of the track somewhere. Keep your views and view models descriptive and specific. If you have many similar view models the issue is probably a bigger design problem; some designers have a tendency to reinvent rather than reuse existing graphical structures.

Naming Conventions Regarding View Models to Avoid Long Names

3 Answers3