LINQ In Line Property Update During Join

Question

I have two obects, A & B for this discussion. I can join these objects (tables) via a common relationship or foreign key. I am using linq to do this join and I only want t

Answer 1

From the word "tables", it sounds like you are getting this data from a database. In which case; no: you can't do this. The closest you can do would to select the objects and the extra columns, and update the properties afterwards:

var qry = from objectA in GetObjectAs()
          join objectB in GetObjectBs()
             on objectA.Id equals objectB.AId
          select new { A = objectA,
              objectB.SomeProp, objectB.SomeOtherProp };

foreach(var item in qry) {
    item.A.SomeProp = item.SomeProp;
    item.A.SomeOtherProp = item.SomeOtherProp;
    // perhaps "yield return item.A;" here
}

If you were doing LINQ-to-Objects, there are perhaps some hacky ways you could do it with fluent APIs - not pretty, though. (edit - like this other reply)