ForEachAsync Example

/*
  To address trouble with...
      myList.ForEach( async x => ...do async work... )
  where control returns before async operations are complete,
  consider...
*/

namespace Example
{
  public static async Task ForEachAsync<T>( this IEnumerable<T> list, Func<T, Task> func )
  {
      await 
          Task.WhenAll(
              list.Select( 
                  item => 
                      Task.Run( () => func(item) )));
  }
}

/*
  The failing...
      myList.ForEach( async x => ...do async work... )
  ...becomes...
      await myList.ForEachAsync( async x => ...do async work... )
  ... and successfully awaits until all tasks are completed.
  
  BONUS! .ForEachAsync() is used fluently with the await/async keywords and is as readable as .ForEach().
*/

Thanks Keboo. Updated from IList to IEnumerable parameter. Will compare against TPL Parallel.ForEach and revisit.