c# - How can I extract a list of Tuple from a specific table with Entity Framework / LINQ? -


i need extract list of couple 'id'/'name' large table in c# .net entity framework.

i try request :

list<tuple<int, string>> list = (from res in db.resource                                   select new tuple<int, string>(res.resource_id, res.name)).tolist();

but unfortunately i've got error :

only parameterless constructors , initializers supported in linq entities.

i don't undestand how can extract list of tuple framework , feel bit lost error. can me understand , resolve problem ?

best regards,

alex

you can middle-step selecting anonymous type:

db.resource.select(x => new { x.resource_id, x.name }).asenumerable().select(x => tuple.create(x.resource_id, x.name)).tolist();

creating tuple not supported operation in linq entities, have select anonymous type, equivalent to:

select [resource].[resource_id], [resource].[name]

then move linq objects asenumerable , tuple.


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