The include
does not work after I perform a select on the IQueryable
query.
Is there a way around this? My query is
public IQueryable<Network> GetAllNetworks()
{
var query = (from n in _db.NetworkSet
.Include("NetworkContacts.Contact")
.Include("NetworkContacts.Contact.RelationshipSource.Target")
.Include("NetworkContacts.Contact.RelationshipSource.Source")
select (n));
return query;;
}
I then try to populate my ViewModel in my WebUI layer using the following code
var projectedNe开发者_StackOverflow中文版tworks =
from n in GetAllNetworks()
select new NetworkViewModel
{
Name = n.Name,
Contacts = from contact in networkList
.SelectMany(nc => nc.NetworkContacts)
.Where(nc => nc.Member == true)
.Where(nc => nc.NetworkId == n.ID)
.Select(c => c.Contact)
select contact,
};
return projectedNetworks;
The problem now occurs in my newly created NetworkViewModel
;
the Contacts
collection objects do not include any loaded data for RelationshipSource.Target
or RelationshipSource.Source
.
However the data is there when run from the original Repository IQueryable
method. However the related include
data does not seem to get transferred into the new Contacts
collection that is created when I use the Select New NetworkViewModel {}
.
Is there a way to preserve this Include
data when it gets passed into a new object? At the moment I just keep getting Null
exceptions
Here's an explanation of what's happening, with a workaround.
In your case, however, I think there's a better workaround than what's in that linked article. You're already using a view model for Network
. That's good! Do it for contact (and it's related properties), too, and your problems with eager loading will magically go away. Projection always works.
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