public async Task SearchAsync()
{
// Cancel any existing continuous search operation.
OverallSearchCancellationTokenSource?.Cancel();
if (SearchTask != null)
{
await SearchTask.CatchExceptions(NU);
}
// Create a CancellationTokenSource for the search we're about to perform.
BeginListening();
OverallSearchCancellationTokenSource = CancellationTokenSource.CreateLinkedTokenSource(ListeningTask_CancellationTokenSource.Token);
SearchTask = SearchAsync(null, OverallSearchCancellationTokenSource.Token);
await SearchTask;
}