Task.Factory.StartNew doesn't throw unhandled exception

Question

I Have the following code, the exception thrown by methodThatThrowsException get silent, how can I throw the exception ?

TaskScheduler scheduler = TaskScheduler.FromCurrentSynchronizationContext();
CancellationToken token = new CancellationToken();

Task task = Task.Factory.StartNew(MethodThatThrowsException)
                        .ContinueWith(t => { throw t.Exception; }, token, TaskContinuationOptions.OnlyOnFaulted, scheduler)
                        .ContinueWith(w => Vm.StatusMessage.StopProgressBar(), token, TaskContinuationOptions.OnlyOnRanToCompletion, scheduler);

Please see Exception Handling in TPL at; https://msdn.microsoft.com/en-us/library/dd997415%28v=vs.110%29.aspx — Teoman shipahi, May 19 '15 at 20:19
Why the downvotes, it's been 2 hours that i'm looking for a solution, couln't find the answer on Stack Overflow or else where? Thanks to give the reason for downvotes so I can edit my question accordingly.. — Anas, May 19 '15 at 20:39
Seems like if you google your question with your exact title you will get this SO answer http://stackoverflow.com/questions/6982294/why-doesnt-my-process-terminate-when-task-has-unhandled-exception and it has same reference link that I gave you. — Teoman shipahi, May 19 '15 at 20:42

score 1 · Answer 1 · answered May 19 '15 at 20:25

You can receive the exception of the task by accessing the task.Exception property.

   Task task = Task.Factory.StartNew(MethodThatThrowsException)
                    .ContinueWith(t => { throw t.Exception; }, token, TaskContinuationOptions.OnlyOnFaulted, scheduler)
                    .ContinueWith(w => Vm.StatusMessage.StopProgressBar(), token, TaskContinuationOptions.OnlyOnRanToCompletion, scheduler);

   System.Exception yourException = task.Exception;

Task.Factory.StartNew doesn't throw unhandled exception

1 Answers1