表示层逻辑和服务/实体

Question

I have a .net webform 'NewShift.ascx' file. It provides you an interface to add information about a new shift you'll be working (or just worked). So things like how many hours you worked, your shift manager, etc. In my code behind I'd like to change the date created label's text to be the current date (DateTime.Now) if and only if it's before 5pm today, otherwise make the date read tomorrow (for reasons I won't go into).

In addition, I might want to format the date a certain way based upon the user (for example if they're associated w/ one culture vs. another as per settings saved in the database, not the current country they are browsing the site in).

You could argue because it's such simple logic, I could just write it out in the code behind, but let's say I had a lot of these little simple things going on (changing values, formatting dates, displaying values based on logic, etc).

My understanding is this would be the smart UI anti-pattern if I did all of this in the code behind. Where should the above logic be?

I hear about not having an anemic domain model and making sure my entities can provide functionality for answering domain-specific questions (?). I also hear about leveraging service layers as much as possible for things as well.

So if I had to do the following:

1. Change a label's text to either today, or tomorrow, based on X and Y
2. Add two values together and assign a label text to that sum based on a user preference
3. conditionally hide a checkbox based upon the day of the week

Where should logic like this be? On the Shift object? Or some sort of _shiftService?

Thanks!

Answer 1

1. Change a label's text to either today, or tomorrow, based on X and Y
2. conditionally hide a checkbox based upon the day of the week

Both of these are obviously presentation concerns. This means that the UI control (ascx file) should make these decisions. You could add a converter if it makes sense, see IValueConverter Interface for more details. It is built for Windows Forms, but you can adapt something similar for the web. Especially using web forms, I find that this clears up the markup substantially.

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2. Add two values together and assign a label text to that sum based on a user preference

It would really depend on what these two values are. If these values are on your model and you just need to show a sum of them and that sum only makes sense to the presentation and not to the business process, this would be a presentation concern and you would either use a converter in your markup or, if you're following MVVM, you would put that summary in your view model under a property of a new name.

If the sum of the two values are part of some business process, then that code should be in your domain and should return a model that already has the sum.