How to query Entity Framework objects where select is a list

Question

I am trying to do something simple, but I can't figure it out. Using EF6, I have 2 tables which are associated by an intermediate associative table, giving a many-to-many relationship:

2 associated tables Users and Families

I want to query all users who belong to a list of families. So I get an array of families:

var db = new MyProjectEntities(); 
User user = GetUserById((int)HttpContext.Current.Session["CurrentUserId"]);
var families = db.Users.Where(u => u.UserId == user.UserId).First().Families.ToArray();

Then I want to query all users belonging to these families:

var users = db.Users.Where(u => families.Contains(u.Families));

But I get this error:

Instance argument: cannot convert from 'Database.Family[]' to 'System.Linq.IQueryable>'

Thanks in advance.

Razvan Dumitru · Accepted Answer · 2019-07-16 09:48:20Z

2

You can use Any method:

var users = db.Users.Where(u => u.Families.Any(fam => families.Contains(fam))).AsEnumerable();

I think this is what you're searching for.

edited Jul 16, 2019 at 9:48

answered Nov 12, 2014 at 14:01

Razvan Dumitru

12.5k5 gold badges38 silver badges55 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Michael Klassen Over a year ago

I just had to insert .AsEnumerable() to avoid the 'Unable to create a constant value of type ...' error.

Razvan Dumitru Over a year ago

Yea it must be enumerated, sorry for ambiguity

Collectives™ on Stack Overflow

How to query Entity Framework objects where select is a list

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related