In my repository implementation I can run the following query using a lambda expression:
public IList<User> GetUsersFromCountry(string)
{
return _UserRepository.Where(x => x.Country == "Sweden").ToList();
}
So far so good, simple stuff. However, I'm having difficulties to write a lambda expression against a nested -> nested list. Given the following example (sorry couldn't think of a better one):
The following query works absolutely fine and returns all clubs, which have members over the age of 45
public IList<Clubs> GetGoldMembers()
{
var clubs = from c in ClubRepository
from m in c.Memberships
where m.User.Age > 45
开发者_运维百科 select c;
return clubs;
}
At the moment, this is where my knowledge of lambda expression ends.
How could I write the above query against the ClubRepository, using a lambda expression, similar to the example above?
This might work (untested)...
var clubs = ClubRepository.Where(c=>c.MemberShips.Any(m=>m.User.Age > 45));
Here's one way to do it:
var clubs = clubRepository
.SelectMany(c => c.Memberships, (c, m) => new { c, m })
.Where(x => x.m.User.Age > 45)
.Select(x => x.c);
A more generic way
List<T> list= new List<T>();
list= object1.NestedList1.SelectMany(x => x.NestedList2).ToList();
Where NestedList2 matches the data type of "list"
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