public OpcRequest Remove()
{
mtx.WaitOne();
OpcRequest req = (OpcRequest)reqQueue.Dequeue();
mtx.ReleaseMutex();
return(req);
}
//-----------------------------------------------------
// Thread that dequeues the requests and makes the OPC server access
private void OpcAccessThread()
{
for (; ;) // Thread loop
{
if (Requests.Count() > 0)
{
OpcRequest req = Requests.Remove();
// An item value is read and displayed in the defined TextBox.
if (req.Cmd == Command.Read)
{
OPCItemState val;
int rtc = SioGrp.Read(OPCDATASOURCE.OPC_DS_CACHE, req.ItemID, out val);
if (HRESULTS.Failed(rtc))
{
Console.WriteLine("Read failed with error 0x" + rtc.ToString("X"));
}
else
{
if (HRESULTS.Failed(val.Error))
{
Console.WriteLine("Read failed with error 0x" + val.Error.ToString("X"));
}
else
{
Console.WriteLine(val.DataValue.ToString(), req.TxtBox);
}
}
}
// A value is written to the OPC server item
else if (req.Cmd == Command.Write)
{
int rtc = SioGrp.Write(req.ItemID, req.Val);
if (HRESULTS.Failed(rtc))
{
Console.WriteLine("Write failed with error 0x" + rtc.ToString("X"));
}
}
}
Thread.Sleep(100); // ms
if (StopThread != null) // Thread kill request
{
StopThread.Set();
return; // terminate the thread
}
}
}
//---------------------------------------------------------------
// Queue OPC server access request
public void Request(OpcRequest req)
{
if (SioGrp == null)
{
return;
}
try
{
int rtc = SioGrp.Write(req.ItemID, req.Val);
if (HRESULTS.Failed(rtc))
{
Console.WriteLine("Write failed with error 0x" + rtc.ToString("X"));
}
}
catch (Exception errmsg)
{
}
//Requests.Add(req);
}
public void Add(OpcRequest req)
{
mtx.WaitOne();
reqQueue.Enqueue(req);
mtx.ReleaseMutex();
}
