The view model in asp.net mvc Diaries

Another solution that we could use is a person generally often called the "ViewModel" pattern. When making use of this pattern we build strongly-typed lessons that happen to be optimized for our distinct view scenarios, and which expose properties for that dynamic values/articles necessary by our view templates.

(all I do know is They may be utilized to go some form of information from controller to view) and maybe explain to me on what problem need to I exploit ViewData in place of ViewModel and vice versa

You should not use the area (business enterprise) entities in the view model. If you are doing, a view model is really worthless since it stills contains business logic which you won't want from the view. The model as part of your case in point won't genuinely stand for an actual-planet scenario, a view model is not likely necessary for it in any case.

A more widespread and trivial illustration of a view model can be a login form: You most likely have a site model known as Consumer and you want them to log in. The Consumer area model can be massive and just a little A part of it is required with the authentication. Additionally, it has validation logic for the database which doesn't characterize validation logic for the login type.

I locate myself employing ViewModels to move the information into a view/type, after which transferring that info into a valid Model when the form posts again into the controller - also pretty useful for storing Lists(IEnumerable).

Checking out the above two lessons we could see that A method to think about a view model is that it's a presentation model that contains another presentation model to be a house.

The Html.DropDownList() helper system previously mentioned will take two parameters. The very first is the identify in the HTML form ingredient to output. The next will be the "SelectList" model we handed by way of the ViewData dictionary. We've been using the C# "as" keyword to Solid the type in the dictionary like a SelectList.

At last I increase the pvm item with the many values on the ProjectEmployeeslist object which might hold objects of type ProjectViewModel after which you can go the model to your view.

As It's really a view model, we prefixed the phrase ViewModel. Even though it is not obligatory to stick to this naming Conference, I personally prefer to observe it to organize view models.

Presented this circumstance you'll only have this just one price/house inside the view model and not all the Attributes that happen to be from the domain item.

Utilizing ViewModels in MVC for finer granularity and far better SoC contributes to a lot more very easily maintainable and testable code. Don't forget, unit screening is about testing little units

In conjunction with far view model in asp.net mvc better coding tactics, there are several company good reasons demonstrating why you may think about using ViewModels:

Frequently contain Homes of a special foundation form than a DTO. For instance, greenback quantities can be represented as strings so they can contain commas in addition to a currency image.

It won't subject in case you implicitly return the ViewResult with return View(); or explicitly pass the view identify to your View strategy with return View("");. In the two instances, view discovery lookups for your matching view file On this order: