/// <summary>
/// Cslled to send refresh events to client.
/// </summary>
private void DoRefresh(object state)
{
try
{
// check if disposed.
if (m_disposed)
{
return;
}
// send a dummy callback after a cancel.
if (state == null)
{
IComAeEventCallback callback = m_callback;
if (callback != null)
{
callback.OnEvent(
ClientHandle,
true,
true,
null);
}
return;
}
Queue <AeEvent> eventsToSend = null;
lock (m_lock)
{
// check if refresh has been cancelled.
if (!Object.ReferenceEquals(state, m_refreshQueue))
{
return;
}
// clear the queue to indicate operation is complete.
eventsToSend = m_refreshQueue;
m_refreshQueue = null;
}
// send the events to client.
SendInBlocks(m_callback, eventsToSend, MaxSize, true);
}
catch (Exception exception)
{
Utils.Trace(exception, "Error processing refresh callback.");
}
}
/// <summary>
/// Sets the callback.
/// </summary>
/// <param name="callback">The callback.</param>
public void SetCallback(IComAeEventCallback callback)
{
ThrowIfDisposed();
lock (m_lock)
{
if (m_callback != null)
{
m_callback.Dispose();
m_callback = null;
}
m_callback = callback;
}
}
/// <summary>
/// Sends the queued events in blocks.
/// </summary>
private void SendInBlocks(IComAeEventCallback callback, Queue <AeEvent> events, uint blockSize, bool refreshFlag)
{
if (callback == null)
{
return;
}
if (blockSize == 0)
{
blockSize = (uint)events.Count;
}
while (events.Count > 0)
{
List <ONEVENTSTRUCT> eventsInBlock = new List <ONEVENTSTRUCT>();
try
{
for (int ii = 0; ii < blockSize && events.Count > 0; ii++)
{
// warning - Translate() allocates unmanaged memory that is deleted in the finally block.
eventsInBlock.Add(Translate(events.Dequeue()));
}
// invoke callback.
callback.OnEvent(
ClientHandle,
refreshFlag,
(refreshFlag)?events.Count == 0:false,
eventsInBlock.ToArray());
}
finally
{
// must deallocate attributes on exit.
for (int ii = 0; ii < eventsInBlock.Count; ii++)
{
IntPtr pAttributes = eventsInBlock[ii].pEventAttributes;
ComUtils.GetVARIANTs(ref pAttributes, eventsInBlock[ii].dwNumEventAttrs, true);
}
}
}
}
/// <summary>
/// Sends the queued events in blocks.
/// </summary>
private void SendInBlocks(IComAeEventCallback callback, Queue<AeEvent> events, uint blockSize, bool refreshFlag)
{
if (callback == null)
{
return;
}
if (blockSize == 0)
{
blockSize = (uint)events.Count;
}
while (events.Count > 0)
{
List<ONEVENTSTRUCT> eventsInBlock = new List<ONEVENTSTRUCT>();
try
{
for (int ii = 0; ii < blockSize && events.Count > 0; ii++)
{
// warning - Translate() allocates unmanaged memory that is deleted in the finally block.
eventsInBlock.Add(Translate(events.Dequeue()));
}
// invoke callback.
callback.OnEvent(
ClientHandle,
refreshFlag,
(refreshFlag)?events.Count == 0:false,
eventsInBlock.ToArray());
}
finally
{
// must deallocate attributes on exit.
for (int ii = 0; ii < eventsInBlock.Count; ii++)
{
IntPtr pAttributes = eventsInBlock[ii].pEventAttributes;
ComUtils.GetVARIANTs(ref pAttributes, eventsInBlock[ii].dwNumEventAttrs, true);
}
}
}
}
/// <summary>
/// Sets the callback.
/// </summary>
/// <param name="callback">The callback.</param>
public void SetCallback(IComAeEventCallback callback)
{
ThrowIfDisposed();
lock (m_lock)
{
if (m_callback != null)
{
m_callback.Dispose();
m_callback = null;
}
m_callback = callback;
}
}
/// <summary>
/// Called send events to client.
/// </summary>
private void DoProcessQueue(object state)
{
Queue <AeEvent> events = new Queue <AeEvent>();
try
{
// check if disposed.
if (m_disposed)
{
return;
}
// process the queue.
lock (m_queue)
{
while (m_queue.Count > 0)
{
events.Enqueue(m_queue.Dequeue());
}
}
// check if time for a keep alive.
lock (m_lock)
{
// check if time for keep alive.
if (events.Count == 0)
{
if (KeepAlive == 0 || m_lastUpdateTime.AddMilliseconds(KeepAlive * m_keepAliveCount) > DateTime.UtcNow)
{
return;
}
}
// no keep alives if not active.
if (!Active)
{
return;
}
// update counters.
if (events.Count > 0)
{
m_lastUpdateTime = DateTime.UtcNow;
m_keepAliveCount = 1;
}
else
{
m_keepAliveCount++;
}
}
// send a keep alive callback.
if (events.Count == 0)
{
IComAeEventCallback callback = m_callback;
if (callback != null)
{
callback.OnEvent(
ClientHandle,
false,
false,
null);
}
return;
}
// send the events to client.
SendInBlocks(m_callback, events, MaxSize, false);
}
catch (Exception exception)
{
Utils.Trace(exception, "Error processing event callback.");
}
}
