How to join 2 tables using linq but avoid anonymous object

Question

I want to join 2 tables using linq and avoid anonymous object.

So far i use tuple.

var products = from tm in db.TargetMarkets
                join tp in db.Products on tm.product_id equals tp.id
                where tm.country == 2
                select Tuple.Create<TargetMarket, Product>(tm, tp);

But, when i foreach

foreach (var p in products)
{
    var a = p.Item1.id;
}

It throws an exception

LINQ to Entities does not recognize the method 'System.Tuple`2

Question:

Is there a way to keep my code strongly typed
What's wrong with tuple (optional)

I suspect error is because of types used join condition, can you check both Ids are of same type? — Hari Prasad
– Hari Prasad, Commented Jan 29, 2016 at 5:37
You notice error in foreach because the first statement is deferred exectution. — Hari Prasad
– Hari Prasad, Commented Jan 29, 2016 at 5:38
They are same types (integer). query statement not throwing the error. foreach execution throws the error. — Pasindu
– Pasindu, Commented Jan 29, 2016 at 5:42

Community · Accepted Answer · 2017-05-23 12:30:59Z

4

Is there a way to keep my code strong type

You can define a new type and make object of that type instead of anonymous object.

class ProductTargetMarket
{
   //Attributes
} 

var ProductsTargetMarkets = from tm in db.TargetMarkets
            join tp in db.Products on tm.product_id equals tp.id
            where tm.country == 2
            select new ProductTargetMarket{Attribute1OfProductTargetMarket = tp.Attribute1, Attribute1OfProductTargetMarket = tm.Attribute1 };

To create a tuple you may first convert it to anonymous type and then convert it to tuple, see this this and this post.

edited May 23, 2017 at 12:30

CommunityBot

11 silver badge

answered Jan 29, 2016 at 5:33

Adil

148k25 gold badges217 silver badges207 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Pasindu Over a year ago

Thanks. it works!. i just wondering "linq query" syntax for, first return anonymous type and convert it to tuple. (optional & googled) :)

Collectives™ on Stack Overflow

How to join 2 tables using linq but avoid anonymous object

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related