Creating a custom aggregator for a PLINQ query

This recipe shows how to create a custom aggregation function for a PLINQ query.

Getting ready

To step through this recipe, you will need Visual Studio 2012. There are no other prerequisites. The source code for this recipe can be found in BookSamples\Chapter7\Recipe6.

How to do it...

To understand the workings of custom aggregation function for a PLINQ query, perform the following steps:

1. Start Visual Studio 2012. Create a new C# Console Application project.

2. In the Program.cs file add the following using directives:

   using System;
   using System.Collections.Concurrent;
   using System.Collections.Generic;
   using System.Linq;
   using System.Threading;

3. Add the following code snippet below the Main method:

   static ConcurrentDictionary<char, int> AccumulateLettersInformation(ConcurrentDictionary<char, int> taskTotal , string item)
   {
     foreach (var c in item)
     {
       if (taskTotal.ContainsKey(c))
       {
         taskTotal[c] = taskTotal[c] + 1;
       }
       else...