Question

I have 2 ActionResults that return the same view with a DropDownList source

Public ActionResult Create()
{
    var model = new ViewModel {
        Entity = new Entity(),
        Categories = GetCategories()
    };

    return View("Edit", model);
}

Public ActionResult Edit(int id)
{
    var model = new ViewModel {
        Entity = GetFromDatabase(id),
        Categories = GetCategories()
    };

    return View(model);
}

I feel like I’m breaking the DRY principle, even if I’ve moved the population of the categories to a method. Is there a better way to go about this and only state where to get the Categories from once?

Answer 1

I think you are bit over concerned. This code looks fine for me. This is more readable. As long as you don’t have a a big performance issue, you don’t need to worry about that.

If you still want to avoid GetCategories call in 2 places and you may put that into the constructor of your ViewModel class.

public class ViewModel
{
  public ViewModel()
  {
  }
  public ViewModel(bool includeCategories)
  {
    this.Categories=SomeService.GetCategories();
  }

  public List<SelectListItem> Categories { set;get;}
  //other properties
}

It is up to you how to handle this. There are no written rules. Follow what you think is more readable and look clean. But personally, i would keep my ViewModel as simple POCO class without any of this constructor logic to load data. I would be happy with calling GetCategories in both the action methods. To me, that looks clean and readable.