/// <summary>
/// Adds items to the subscription.
/// </summary>
public void AddItems(
ItemList requestList,
SubscribeItemValueResult[] replyList,
bool returnValues,
ItemResult[] additemResults)
{
lock (this)
{
ArrayList indexes = new ArrayList();
ArrayList items = new ArrayList();
for (int ii = 0; ii < requestList.Count; ii++)
{
Item item = new Item(requestList[ii]);
// check item path.
if ((item.ItemPath != null && item.ItemPath != ItemPath) || (item.ItemPath == null && requestList.ItemPath != ItemPath))
{
continue;
}
// check sampling rate.
if ((item.SamplingRateSpecified && item.SamplingRate != UpdateRate) || (!item.SamplingRateSpecified && requestList.SamplingRate != UpdateRate))
{
continue;
}
// check deadband.
if ((item.DeadbandSpecified && item.Deadband != Deadband) || (!item.DeadbandSpecified && requestList.Deadband != Deadband))
{
continue;
}
// assign globally unique client handle.
item.ClientHandle = item.ItemName + Guid.NewGuid().ToString();
if (item.ReqType == null && requestList.ReqType != null)
{
item.ReqType = requestList.ReqType;
}
// item can be handled by this subscription.
indexes.Add(ii);
// copy the item and clear the item path.
Item copy = new Item(item);
copy.ItemPath = null;
items.Add(copy);
}
// check if no suitable items found.
if (indexes.Count == 0)
{
return;
}
// add items to subscription.
ItemResult[] results = m_subscription.AddItems((Item[])items.ToArray(typeof(Item)));
ItemValueResult[] values = null;
if (returnValues)
{
values = m_subscription.Read(results);
}
// fill-in result list.
for (int ii = 0; ii < items.Count; ii++)
{
int index = (int)indexes[ii];
// return the add item result.
additemResults[index] = results[ii];
Item item = (Item)items[ii];
SubscribeItemValueResult result = new SubscribeItemValueResult();
result.ItemName = item.ItemName;
result.ItemPath = ItemPath;
result.ClientHandle = requestList[index].ClientHandle;
result.ServerHandle = results[ii].ServerHandle;
result.SamplingRate = 0;
result.SamplingRateSpecified = false;
result.Value = null;
result.Quality = Quality.Bad;
result.QualitySpecified = false;
result.Timestamp = DateTime.MinValue;
result.TimestampSpecified = false;
result.ResultID = results[ii].ResultID;
result.DiagnosticInfo = results[ii].DiagnosticInfo;
if (results[ii].SamplingRateSpecified && results[ii].SamplingRate != item.SamplingRate)
{
result.SamplingRate = results[ii].SamplingRate;
result.SamplingRateSpecified = results[ii].SamplingRateSpecified;
}
if (values != null)
{
if (result.ResultID.Succeeded())
{
result.Value = values[ii].Value;
result.Quality = values[ii].Quality;
result.QualitySpecified = values[ii].QualitySpecified;
result.Timestamp = values[ii].Timestamp;
result.TimestampSpecified = values[ii].TimestampSpecified;
result.ResultID = values[ii].ResultID;
result.DiagnosticInfo = values[ii].DiagnosticInfo;
}
}
// return the value as part of the subscribe response.
replyList[index] = result;
// save server handle locally.
if (result.ResultID.Succeeded())
{
m_items[(string)item.ClientHandle] = new ItemIdentifier(results[ii]);
}
}
}
}
/// <summary>
/// Initializes the object by creating the remote subscription.
/// </summary>
public bool Initialize(
string locale,
Hashtable servers,
ItemList requestList,
SubscribeItemValueResult[] replyList,
bool returnValues,
ItemResult[] results)
{
lock (this)
{
// find first item that has not been assigned to a subscription.
Item item = null;
int index = -1;
for (int ii = 0; ii < requestList.Count; ii++)
{
if (replyList[ii] == null)
{
item = (Item)requestList[ii];
m_itemPath = (item.ItemPath != null)?item.ItemPath:requestList.ItemPath;
m_updateRate = (item.SamplingRateSpecified)?item.SamplingRate:requestList.SamplingRate;
m_deadband = (item.DeadbandSpecified)?item.Deadband:requestList.Deadband;
index = ii;
break;
}
}
// no items found.
if (item == null)
{
return(false);
}
// look up the remote server.
m_server = null;
if (m_itemPath != null)
{
m_server = (Opc.Da.IServer)servers[m_itemPath];
}
// check for invalid item path.
if (m_server == null)
{
// create error result.
results[index] = new ItemResult(item, ResultID.Da.E_UNKNOWN_ITEM_PATH);
// create subscribe response.
SubscribeItemValueResult result = new SubscribeItemValueResult(item);
result.ItemPath = m_itemPath;
result.ResultID = ResultID.Da.E_UNKNOWN_ITEM_PATH;
replyList[index] = result;
return(false);
}
// create the subscription.
try
{
SubscriptionState state = new SubscriptionState();
state.Name = null;
state.Active = true;
state.UpdateRate = m_updateRate;
state.Deadband = m_deadband;
state.Locale = locale;
state.KeepAlive = 0;
m_subscription = (Opc.Da.ISubscription)m_server.CreateSubscription(state);
}
catch (Exception e)
{
if (m_subscription != null)
{
m_subscription.Dispose();
m_subscription = null;
}
m_server = null;
throw e;
}
// add items.
AddItems(requestList, replyList, returnValues, results);
return(true);
}
}
