Select all Items which intersect

Question

I would like to get all values which Intersect from this LINQ query:

Where(x => x.Attribute("name").Value).Intersect(myList).Any();

I don't know how to add a select.

Assuming the Where is being applied to a collection of `T` do want your result to be a collection of `T` or a collection of the type of `T.Attribute("name").Value`? — Bob Vale, Jul 05 '12 at 10:16

Bob Vale · Accepted Answer · 2012-07-05T12:50:50.733

2

I'm assuming the you want all the Attribute("name").Value that are in myList

You can either do

Where(x=>myList.Contains(x.Attribute("name").Value)).Select(x=>x.Attribute("name").Value)

or

Select(x=>x.Attribute("name").Value).Intersect(myList)

edited Jul 05 '12 at 12:50

answered Jul 05 '12 at 10:48

Bob Vale

The second answer gets and error: _Cannot convert lambda expression to delegate type 'System.Func' because some of the return types in the block are not implicitly convertible to the delegate return type._ Is there any solution because it seems a easier solution. (First works) – Daniel Camacho Jul 05 '12 at 10:53
@kmxillo I did a typo, missed the `x=>`. I've updated the answer – Bob Vale Jul 05 '12 at 10:57

abatishchev · Answer 2 · 2012-07-05T10:38:59.457

1

Why do you do intersection? Why don't just List.Contains?

data.Where(x => myList.Contains(x.Attribute("name").Value).ToList();

or

data.Select(x => x.Attribute("name").Value).Intersect(myList);

edited Jul 05 '12 at 10:38

answered Jul 05 '12 at 10:12

abatishchev

x is XElement. How can convert to List because .Value returns String. – Daniel Camacho Jul 05 '12 at 10:25
Sorry but You miss one parentesis. And that solution does not work, – Daniel Camacho Jul 05 '12 at 10:37
@kmxillo: Silly mistake due a hurry. That was a copy-paste. Fixed it now. – abatishchev Jul 05 '12 at 10:39

2 Answers2