Question

For each entity in my repository, I have a view model and an input model. I find having an input model to store relational IDs (as opposed to foreign entities) makes rendering select lists easier, but which model do you pass to your Edit view for rendering, View Model or Input Model?

Sample POST action for Category entity:

[HttpPost]
public ActionResult Edit(CategoryInputModel inputModel)
{
    // map inputModel to entity and persist
    // ...
}

View Model:

[HttpGet]
public ActionResult Edit(int id)
{
    var category = _unitOfWork.CurrentSession.Get<Category>(id);
    var viewModel = Mapper.Map<Category, CategoryViewModel>(category);
    return View(viewModel);
}

In this case the edit view form would take care of providing the correct input model fields for the POST action.

Input Model:

[HttpGet]
public ActionResult Edit(int id)
{
    var category = _unitOfWork.CurrentSession.Get<Category>(id);
    var inputModel = Mapper.Map<Category, CategoryInputModel>(category);
    return View(inputModel);
}

Which is easier to maintain in the long run?

Answer 1

I’m now using an input model that does not contain an ID. I keep the entity ID as the action parameter, like so:

[HttpPost]
public ActionResult Edit(Guid id, CategoryInputModel inputModel)
{
    var category = _categoryRepository.Get(id);
    // do mappings from inputModel to category and save
    // ...
}