using System;

using System.Linq;

using System.Threading;

​

public class Program

{

    public static void Main()

    {

        ParallelQuery<int> query = Enumerable.Range(1, 2)

            .AsParallel()

            .Select(x =>

            {

                if (x == 2) { Thread.Sleep(500); throw new Exception($"Oops!"); }

                return x;

            });

​

        try

        {

            foreach (var item in query)

            {

                Console.WriteLine($"Consuming item #{item} started");

                throw new Exception($"Consuming item #{item} failed");

            }

        }

        catch (AggregateException aex)

        {

            Console.WriteLine($"AggregateException ({aex.InnerExceptions.Count})");

            foreach (var ex in aex.InnerExceptions)

                Console.WriteLine($"- {ex.GetType().Name}: {ex.Message}");

        }

        catch (Exception ex)

        {

            Console.WriteLine($"{ex.GetType().Name}: {ex.Message}");

        }

    }

}

​