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djmurp

•Created by Ab on 2/15/2023 in #help

❔ Design Question

I don't think that would work because of circular references (Application references library, library references application), but you're right to be iffy about that anyway. It would be better design to have the library offer the state via a method, and then the project which contains the Application class (or even the Application class itself) can decide its own fate by calling the method which returns the state and setting it itself. This way the library isn't tied to Application and is now reusable in other places, and also you don't have a library changing state without you telling it when to do it

4 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

or follow the suggestions VS givees

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

you need to change your controller method (FavoritePerson) to return Task<IActionResult> and add the async modifier

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

so basically

var user = await _userManager.GetUserAsync(User);
_context.Entry(user) // lowercase user, NOT "User"!
        .Collection(b => b.People)
        .Load();

var user = await _userManager.GetUserAsync(User);
_context.Entry(user) // lowercase user, NOT "User"!
        .Collection(b => b.People)
        .Load();

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

yeah ignore me. I am confusing @jcotton42 s responses by confusing eager loading with explicit loading, think ill go to sleep now.

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

hmm

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

you cannot explicitly load a navigation property via the user manager GetUserAsync(User) method, so you have to do it alone via the _context

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

see above where I recommended the explicit loading

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

so the line below that line crashes?

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

it's empty because you are going via userManager, something provided to you via Identity. It doesn't automatically know that you want all related data so it gives you the basics (column values). Anything more would result in a lot of SQL JOINs

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

you can investigate it to see if it suits your use case, but feel free to persist and post an update instead

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

another approach would be entity framework lazy loading (in that case accessing .People will trigger additional SQL) but i'd avoid if possible - it's convenient but much less efficient!

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

check this https://stackoverflow.com/questions/39837355/eager-loading-using-usermanager-with-ef-core, the answer for you actually in the question itself

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

I have another code recommendation but we can solve this first

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

yes that should work in a readable way

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

then you will have to query

var userWithPeople = _context.ApplicationUsers.Include(x => x.People).FirstOrDefault(x => x.Id == user.Id);

var userWithPeople = _context.ApplicationUsers.Include(x => x.People).FirstOrDefault(x => x.Id == user.Id);

or similar after the userManager.GetUserAsync(User) call

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

yeh, or the equivalent property name in your context

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

do you know what table your users are in?

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

yep you've done the same thing, it's just that unfortunately you can't .Include that property when calling the built in Identity method - I thought you owned that code but you didn't

85 replies

•Created by KooriByte on 2/5/2023 in #help

✅ Collection appears to be null, even though it's not null on DB

some properties are fine because they are columns in the same user table, but it won't go and get related entities from a different table (like .People)

85 replies