Get first available udp port

.cs

public bool TryGetFirstAvailableUdpPort(out int port)
{
	var startingAtPort = 5678;
	var maxNumberOfPortsToCheck = 500;
	var range = Enumerable.Range(startingAtPort, maxNumberOfPortsToCheck).ToList();
	
	var portsInUse =
		from p in range
		join used in System.Net.NetworkInformation.IPGlobalProperties.GetIPGlobalProperties().GetActiveUdpListeners()
		on p equals used.Port
			select p;

	var firstFreeUdpPortInRange = range.Except(portsInUse).FirstOrDefault();
	if (firstFreeUdpPortInRange > 0)
	{
		port = firstFreeUdpPortInRange;
		return true;
	}

	port = -1;
	return false;
}