Hey so I've got the situation where I'm pulling a client back from the database and including all the case studies with it by way of an include
return (from c in db.Clients.Include("CaseStudies")
where c.Id == clientId
select c).First();
but what I want to do now is and a where clause 开发者_StackOverflow社区on the included casestudies so that it only returns the case studies where deleted = false
sort of like this
return (from c in db.Clients.Include("CaseStudies")
where c.Id == clientId
&& c.CaseStudy.Deleted == false
select c).First();
But this doesn't work :( any ideas
Conditional includes are not supported out-of-the-box in EF v1.0. But Alex James has a bit hacky workaround for that explained well here: http://blogs.msdn.com/alexj/archive/2009/10/13/tip-37-how-to-do-a-conditional-include.aspx
var dbquery =
from c in db.Clients
where c.Id == clientID
select new {
client = c,
caseStudies = from cs in c.CaseStudy
where cs.Deleted==false
select cs
};
return dbquery
.AsEnumerable()
.Select(c => c.client);
Also, I haven't succeeded to make this workaround work with many-to-many relationships.
You can return a similar group of records this way, the GroupBy is going to make the enumeration different, but its not difficult.
CaseStudies.Include("Client")
.Where(c => !c.Deleted && c.Client.ID == ClientID)
.GroupBy(c => c.Client.ID);
One option is to perform a query on your results, like this:
var results = (from c in db.Clients.Include("CaseStudies")
where c.Id == clientId
select c).First();
results.CaseStudies = (from c in results.CaseStudies
where c.Deleted == false
select c).ToList();
Or of course you can use a lambda expression:
var results = db.Clients
.Include(c => c.CaseStudies)
.Where(c => c.ID == clientId).First();
results.CaseStudies = results.CaseStudies.Where(c => !c.Deleted).ToList();
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