TaskContinuationOptions.OnlyOnFaulted与try catch

Question

What's the difference between

var task3 = Task.Run(() => PerformLongTask()).ContinueWith(t => Log.Error(t.Exception), TaskContinuationOptions.OnlyOnFaulted);

and

var task3 = Task.Run(() => PerformLongTask());

private void PerformLongTask()
{
  try
  {
  //......
  }
  catch (Exception ex)
  {
     Log.Error(ex);
  }
}

I tried running both examples. On the surface, they appear to behave the same.

Is one approach better than the other?

Answer 1

In this case, they're the same. However, if you don't own the innards of "PerformLongTask", you can't wrap its contents in a try-catch either. Also, the task's Status will be set to RanToCompletion this way, even if it threw an exception. If you have a continuation on the task, it will have to deal with the antecedent task potentially not having a valid Result.

I suppose the short of it is that in the former case, your exception handling logic is contained in a separate task, decoupled from the rest.