I am using the new async await features to upgrade from backgroundworker in C#. In the following code I am trying to replicate the execution of multiple tasks with ContinueWith method.
Task t1 = new Task
(
() =>
{
Thread.Sleep(10000);
// make the Task throw an exception
MessageBox.Show("This is T1");
}
);
Task t2 = t1.ContinueWith
(
(predecessorTask) =>
{
if (predecessorTask.Exception != null)
{
MessageBox.Show("Predecessor Exception within Continuation");
return;
}
Thread.Sleep(1000);
MessageBox.Show("This is Continuation");
},
TaskContinuationOptions.AttachedToParent | TaskContinuationOptions.OnlyOnRanToCompletion
);
t1.Start();
try
{
t1.Wait(); <------ Comment
t2.Wait(); <------ Comment
}
catch (AggregateException ex)
{
MessageBox.Show(ex.InnerException.Message);
}
My question is when I comment t1.wait and t2.wait Tasks are not blocking UI. However when I uncomment t1.wait and t2.wait UI blocks until thread is completed. The desired behavior is to catch errors in try/catch block without blocking UI. What Am I missing?
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