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c#.net.net-4.0.net-2.0

.net construct for while loop with timeout


I commonly employ a while loop that continues to try some operation until either the operation succeeds or a timeout has elapsed:

bool success = false
int elapsed = 0
while( ( !success ) && ( elapsed < 10000 ) )
{
     Thread.sleep( 1000 );
     elapsed += 1000;
     success = ... some operation ...     
}

I know there a couple of way to implement this, but the basic point is that I repeatedly try some operation with a sleep until success or I've slept too long in aggregate.

Is there a built-in .net class/method/etc to save me from re-writing this pattern all over the place? Perhaps input is an Func(of bool) and the timeout?

Edit
Thanks to all who contributed. I opted for the sleep() approach because it was the least complicated and I'm totally anti-complexity =) Here's my (still needs to be tested) implimentation:

 public static bool RetryUntilSuccessOrTimeout( Func<bool> task , TimeSpan timeout , TimeSpan pause )
    {

        if ( pause.TotalMilliseconds < 0 )
        {
            throw new ArgumentException( "pause must be >= 0 milliseconds" );
        }
        var stopwatch = Stopwatch.StartNew();
        do
        {
            if ( task() ) { return true; }
            Thread.Sleep( ( int )pause.TotalMilliseconds );
        }
        while ( stopwatch.Elapsed < timeout );
        return false;
    }

Solution

  • You could wrap your algorithm in a method:

    public bool RetryUntilSuccessOrTimeout(Func<bool> task, TimeSpan timeSpan)
    {
        bool success = false;
        int elapsed = 0;
        while ((!success) && (elapsed < timeSpan.TotalMilliseconds))
        {
            Thread.Sleep(1000);
            elapsed += 1000;
            success = task();
        }
        return success;
    }
    

    and then:

    if (RetryUntilSuccessOrTimeout(() => SomeTask(arg1, arg2), TimeSpan.FromSeconds(10)))
    {
        // the task succeeded
    }