I am trying to get my head around async/await and thought I did understand few things about the usage. But still not quite clear what would be the actual benefit in a scenario like below.
Look at the Task.Run usage. The first method uses a normal delegate and uses Thread.Sleep but the second one uses 'async' delegate and Task.Delay.
My question is : how does this make any difference to this method (or it does not) ?
The method itself is an async method. The code is creating a separate thread (via Task.Run) and this thread has nothing else to do other than executing that delegate. So, even if it yields with an await on Task.Delay, what is the use in this scenario, since the thread is anyways a isolated thread not used for anything else and even if it just uses Thread.Sleep, the thread would still context switch to yield to other threads for the processor.
// The task thread uses a async delegate
public async Task<bool> RetrySendEmail(MailMessage message)
{
bool emailSent = false;
await (Task.Run(***async ()*** =>
{
for (int i = 0; i < 3; i++)
{
if (emailSent)
break;
else
// Wait for 5 secs before trying again
***await Task.Delay(5000);***
try
{
Smtphost.Send(message);
emailSent = true;
break;
}
catch (Exception e) { emailSent = false; // log; }
}
return emailSent;
}));
}
// The task thread uses a normal delegate
public async Task<bool> RetrySendEmail(MailMessage message)
{
bool emailSent = false;
await (Task.Run(***()*** =>
{
for (int i = 0; i < 3; i++)
{
if (emailSent)
break;
else
// Wait for 5 secs before trying again
***Thread.Sleep(5000);***
try
{
Smtphost.Send(message);
emailSent = true;
break;
}
catch (Exception e){ emailSent = false; // log; }
}
return emailSent;
}));
}
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