Combine LINQ queries?

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Hi all,

I'm both new to C# and LINQ and finding it a steep hill to climb! I don't know how to build this particular LINQ query and have broken it down into two separate parts to get it to work.
I'm sure I should be able to combine them but its beyond my knowledge at the moment.

Anyway, to the problem. I have WmsUser class which contains a WMSUserGroup class, and hanging from this is a WmsUserGroupDepotCollection, each member of which contains a permissions collection. Currently I'm retrieving the permissions class in two hits, first by fetching WmsUserGroupDepot from the WmsUserGroupDepotCollection using the DepotId contained within my boundObject. Then retreiving the WmsUserGroupDepotPermission from the WmsUserGroupDepot. Can anyone help me by showing how to combine the two statements?

Thanks in advance
Dave

C#

WmsUserGroupDepot ugDepot=(
from o in ((App)App.Current).WmsUser.WmsUserGroup.WmsUserGroupDepotCollection
where o.DepotId == boundObject.DepotId
select o).SingleOrDefault();

WmsUserGroupDepotPermission depotPermission = 
(from o in ugDepot.WmsUserGroupDepotPermissionCollection
where o.SectionId == (long)PermissionsSectionEnum.Setup
select o).SingleOrDefault();

Posted 27-Feb-13 4:36am

David Yemm

Updated 27-Feb-13 5:12am

Orcun Iyigun

v2

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BC @ CV · Answer 1 · 2013-02-27T05:47:00

Yes you can make this into one query, even a one liner. I'm not sure that you need to but you could do it any of these ways.

C#

var depotPermission = WmsUser.WmsUserGroup.WmsUserGroupDepotCollection
                      .SingleOrDefault(x=>x.DepotId==boundObject.DepotId)
                      .WmsUserGroupDepotPermissionCollection
                      .SingleOrDefault(p=>p.SectionId== (long)PermissionsSectionEnum.Setup);

Or

C#

var depotPermission = from o in WmsUser.WmsUserGroup.WmsUserGroupDepotCollection
                      where o.DepotId == boundObject.DepotId
                      select o.WmsUserGroupDepotPermissionCollection
                      .SingleOrDefault(x=>x.SectionId == (long)PermissionsSectionEnum.Setup);

Or

C#

var depotPermission = from o in WmsUser.WmsUserGroup.WmsUserGroupDepotCollection
                      where o.DepotId == boundObject.DepotId 
                      select (from p in o.WmsUserGroupDepotPermissionCollection 
                            where p.SectionId == (long)PermissionsSectionEnum.Setup
                            select p
                            );

For your future reference: 101 Linq Samples

Combine LINQ queries?

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Combine LINQ queries?

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