is it possible to use Take in LINQ when the query returns an anonymous type?

Question

I'm trying to get the n-th element out of a list of anonymous types returned by a LINQ query where n is a random number from 0 to 100. Messed around with it a while now and I'm not getting anywhere. My code (with names changed to protect IP):

var query = from Table1 t1 in theContext.Table1 
   join Table2 t2 in theContext.Table2
    on ... 
    where ... 
   select new 
   {
       partNum = t1.part_number, 
       partSource = t2.part_source
   }

int num = new Random().Next(0, 100); 

// here's where the code I've tried fails

Can I somehow do a Take<T>(100).ToList<T>()[num] to get a single anonymous type with partNum and partSource? I ended up solving this by explicitly defining a type, but it seemed like I was missing a more elegant solution here. All I want to do is return a Dictionary<string, string> to the caller so I'd prefer not to have to define a type outside of this method.

Update: ElementAt doesn't work for this. I tried adding:

// get a random part from the parts list
int num = new Random().Next(0, query.Count() - 1 );
var nthElement = query.ElementAt(num);

And I got an exception: The query operator 'ElementAt' is not supported.

Answer 1

You should be able to use:

var item = query.Take(100).ToList()[num];

Of course, it would be more efficient to do:

var item = query.Skip(num).First();

Answer 2

I believe you just want the ElementAt extension method:

var nthElement = query.ElementAt(num);

No need to mess with Take queries or such, and certainly not ToList.

Answer 3

Marc nailed it, but if you want numbers from 0 to 100 inclusive, you need:

int num = new Random().Next(0, 101);

Because the Next(int, int) function uses an exclusive upper-bound.