private void RunWaitForTasksToCompleteOneByOne()
{
// this is a good pattern to use when:
// - You are wanting to handle (retry, log error, discard) failed tasks as they happen.
// - when you want to overlapp computation with result processing
int numberOfTasksToRun = 5;
List <Task <string> > listOfTasks = new List <Task <string> >();
SimpleAsyncClass2 SAC2 = new SimpleAsyncClass2();
for (int index = 0; index < numberOfTasksToRun; index++)
{
if (index % 2 == 0)
{
listOfTasks.Add(SAC2.AsyncMethod1());
}
else
{
listOfTasks.Add(SAC2.AsyncMethod2());
}
}
while (listOfTasks.Count > 0)
{
int completedTaskIndex = Task.WaitAny(listOfTasks.ToArray());
// log errors, retry, skip and move on, etc code here
Console.WriteLine(listOfTasks[completedTaskIndex].Result);
listOfTasks.RemoveAt(completedTaskIndex);
}
Console.WriteLine("All tasks complete");
}
private void RunCancellingTasks()
{
CancellationTokenSource cts = new CancellationTokenSource();
CancellationToken ct = cts.Token;
int count = 0;
int numberOfTasksToRun = 3;
List <Task <string> > listOfTasks = new List <Task <string> >();
SimpleAsyncClass2 SAC2 = new SimpleAsyncClass2();
for (int index = 0; index < numberOfTasksToRun; index++)
{
if (index == 0)
{
listOfTasks.Add(SAC2.LongRunningAsyncMethod1(ct));
}
else if (index == 1)
{
listOfTasks.Add(SAC2.LongRunningAsyncMethod2(ct));
}
else if (index == 2)
{
listOfTasks.Add(SAC2.ShortRunningAsyncMethod1(ct));
}
}
while (listOfTasks.Count > 0)
{
int completedTaskIndex = Task.WaitAny(listOfTasks.ToArray());
// log errors, retry, skip and move on, etc code here
Console.WriteLine(listOfTasks[completedTaskIndex].Result);
count++;
// cancel after the second task completes
if (count == 2)
{
// cancel the tasks via the token
Console.WriteLine("Cancelling Tasks");
cts.Cancel();
listOfTasks.Clear();
}
else
{
listOfTasks.RemoveAt(completedTaskIndex);
}
}
Console.WriteLine("All tasks complete");
}
private void RunTaskExceptionHandling3()
{
try
{
Console.WriteLine("taskWithException started");
SimpleAsyncClass2 SAC2 = new SimpleAsyncClass2();
Task failedTask = SAC2.TaskMethodThatWillFail();
failedTask.Wait();
Console.WriteLine("taskWithException complete");
}
catch (AggregateException e)
{
Console.WriteLine("AggregateException: " + e.InnerException.Message);
}
}
private void RunMultiTaskExceptionHandling()
{
try
{
Console.WriteLine("Multi Task Exception started");
SimpleAsyncClass2 SAC2 = new SimpleAsyncClass2();
Task failedTask = SAC2.TaskMethodThatWillFail();
Task failedTask2 = SAC2.TaskMethodThatWillFail2();
Task successfulTask = SAC2.AsyncMethod1();
Task[] taskArray = { failedTask, failedTask2, successfulTask };
Task.WaitAll(taskArray);
Console.WriteLine("Multi Task Exception complete");
}
catch (AggregateException e)
{
foreach (Exception ex in e.InnerExceptions)
{
Console.WriteLine("Tasking Error: " + ex.Message);
}
}
}
public AsyncMenu2()
{
_SAC = new SimpleAsyncClass2();
}
private void RunPassingParametersToAsyncMethod()
{
SimpleAsyncClass2 SAC2 = new SimpleAsyncClass2();
Task parameterTask = SAC2.AsyncMethodWithParameter("some string");
}
