How do you create an asynchronous method in C#?

Question

Every blog post I\'ve read tells you how to consume an asynchronous method in C#, but for some odd reason never explain how to build your own asynchronous methods to consume

Answer 1

I don't recommend StartNew unless you need that level of complexity.

If your async method is dependent on other async methods, the easiest approach is to use the async keyword:

private static async Task CountToAsync(int num = 10)
{
  for (int i = 0; i < num; i++)
  {
    await Task.Delay(TimeSpan.FromSeconds(1));
  }

  return DateTime.Now;
}

If your async method is doing CPU work, you should use Task.Run:

private static async Task CountToAsync(int num = 10)
{
  await Task.Run(() => ...);
  return DateTime.Now;
}

You may find my async/await intro helpful.