Question

I have a linq query that is querying over IEnumberable. When I have a matching element for my where clause I would like to know the position of the element in the IEnumberable.

var result = from e in elements
             where (string) e.Attribute("class") == "something"
             select e.Position();

The e.Position() of course does not compile. The value of e.Position() would be the position of the selected element in the elements IEnumberable.

Any ideas on how to do this?

Answer 1

You need to use the overloaded Select method that allows for an index since that capability is not available in query syntax.

elements.Select((e, i) => new { Element = e, Index = i })
        .Where(item => (string)item.Element.Attribute("class") == "something")
        .Select(item => item.Index);