[C#] Parallel asynchronous execution example

ParallelAsync.md

Parallel asynchronous execution - C# Example

Synchronous

Below we have a synchronous example when each worker counts to 10.

private static List<string> workers = new List<string>(){"A","B","C"};

static void Main(string[] args)
{
  CallWorkers();
  Console.ReadKey();
}

private static void CallWorkers()
{
  foreach (string workerName in workers)
  {
    Work(workerName);
  }
}

private static void Work(string workerName)
{
  for (int i = 0; i < 10; i++)
  {
    Console.WriteLine("WORKER " + workerName+ " - " + (i + 1));
  }
}

Output

WORKER A - 1
WORKER A - 2
WORKER A - 3
WORKER A - 4
WORKER A - 5
WORKER A - 6
WORKER A - 7
WORKER A - 8
WORKER A - 9
WORKER A - 10
WORKER B - 1
WORKER B - 2
WORKER B - 3
WORKER B - 4
WORKER B - 5
WORKER B - 6
WORKER B - 7
WORKER B - 8
WORKER B - 9
WORKER B - 10
WORKER C - 1
WORKER C - 2
WORKER C - 3
WORKER C - 4
WORKER C - 5
WORKER C - 6
WORKER C - 7
WORKER C - 8
WORKER C - 9
WORKER C - 10

The execution of the workers is sequential by the order of call.

Parallel Asynchronous

private static List<string> workers = new List<string>(){"A","B","C"};

static void Main(string[] args)
{
  CallWorkersParallelAsync();
  Console.ReadKey();
}

private static async Task CallWorkersParallelAsync()
{
  List<Task> tasks = new List<Task>();

  foreach (string workerName in workers)
  {
    tasks.Add(Task.Run(() => Work(workerName)));
  }
  await Task.WhenAll(tasks);
}

private static void Work(string workerName)
{
  for (int i = 0; i < 10; i++)
  {
    Console.WriteLine("WORKER " + workerName+ " - " + (i + 1));
  }
}

Output

WORKER A - 1
WORKER A - 2
WORKER A - 3
WORKER A - 4
WORKER A - 5
WORKER A - 6
WORKER A - 7
WORKER A - 8
WORKER A - 9
WORKER A - 10
WORKER B - 1
WORKER B - 2
WORKER B - 3
WORKER B - 4
WORKER B - 5
WORKER C - 1
WORKER C - 2
WORKER C - 3
WORKER C - 4
WORKER C - 5
WORKER C - 6
WORKER C - 7
WORKER C - 8
WORKER C - 9
WORKER C - 10
WORKER B - 6
WORKER B - 7
WORKER B - 8
WORKER B - 9
WORKER B - 10

The execution of the workers is parallel, they are running at the same time. At each run the output can be diffrent.