//Method2: asynchronous pattern using a BeginInvoke, followed by waiting with a time-out
public void GetResultsAndWait(string key, ref List <string> keys_matched, int waitTime = 10000)
{
//declare instance of delegate
GetResultsDelegate getResultDelegate = new GetResultsDelegate(ResultsGetter.GetResults);
//asynchonously invoke the GetResult method
IAsyncResult result = getResultDelegate.BeginInvoke(key, ref keys_matched, null, null);
while (!result.IsCompleted)
{
//do any work that can done before waiting
result.AsyncWaitHandle.WaitOne(waitTime, false);
}
result.AsyncWaitHandle.Close();
//the asynchronous operation has completed
bool return_val = getResultDelegate.EndInvoke(ref keys_matched, result);
}
//Method1: asynchronous pattern using a callback method
public void GetResultUsingCallback(string key, ref List <string> keys_matched)
{
//declare instance of delegate
GetResultsDelegate getResultDelegte = new GetResultsDelegate(ResultsGetter.GetResults);
// Waiter will keep the main application thread from
// ending before the callback completes because
// the main thread blocks until the waiter is signaled
// in the callback
waiter = new ManualResetEvent(false);
//define the AsyncCallback delegate
AsyncCallback callback = new AsyncCallback(this.ResultsReady);
// Asynchronously invoke the GetRsults method
IAsyncResult result = getResultDelegte.BeginInvoke(key, ref keys_matched, callback, key);
// Do some other useful work while
// waiting for the asynchronous operation to complete.
// When no more work can be done, wait.
waiter.WaitOne();
}