c# async wait for event

Describe your methodology here.  What are you trying to accomplish?

The purpose of async/await are to allow you to complete processes asynchrounously.  However, the result of the awaited method blocks it's current method until the awaited method returns its results (or throws an exception).

Proof of concept:

using System;
using System.Threading.Tasks;

namespace EE_Q28820699
{
	class Program
	{
		static void Main(string[] args)
		{
			Task task = new Task(ProcessLinesAsync);
			task.Start();
			task.Wait();
			Console.WriteLine("This line appears before all of the results are processed.");
			while (task.Status == TaskStatus.Running) { ;}
			Console.ReadLine();
		}

		static async void ProcessLinesAsync()
		{
			Console.WriteLine("Testing an awaited result");
			Task task = new Task(HaveSomeFun);
			task.Start();
			task.Wait();
			int x = await ProcessLines();
			Console.WriteLine("Processed {0} lines", x);
			Console.WriteLine("This line appears after the results are processed.");
			Console.WriteLine("Finished processing the task.  Press any key to exit.");
		}

		static async Task<int> ProcessLines()
		{
			int count = 0;
			for (int i = 0; i < 10; i++)
			{
				Console.WriteLine("Processing line {0}...", i);
				// Add a 5 second delay
				await Task.Delay(500);
				count++;
			}
			return count;
		}

		static async void HaveSomeFun()
		{
			for (int i = 0; i < 10; i++)
			{
				Console.WriteLine("Where's waldo? Checking position - {0}", i);
				// Add a 2.5 second delay
				await Task.Delay(250);
			}
		}
	}
}

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If you run the above code you will get results similar to this -Just by observing the output, we can see that the HaveSomeFun method ran asynchronously to the ProcessLinesAsync method (which itself ran asynchronously to the Main method).  And to your point, you are correct, none of this is blocking the main thread because if we were to press a key at any point the program would exit.  The only thing keeping the program alive at this moment is the Console.ReadLine() call which blocks the main thread.

However, we also notice that the following lines, appear only after the awaited result is returned:
'Processed 10 lines'
'This line appears after the results are processed'
and
'Finished processing the task.  Press any key to exit'

-saige-