/// <summary>
/// Moves the current browse position down.
/// </summary>
/// <param name="session">The session.</param>
/// <param name="targetName">Name of the target.</param>
public void BrowseDown(Session session, string targetName)
{
TraceState("BrowseDown", targetName);
// find the id of the current element.
string itemId = null;
lock (m_lock)
{
if (m_browsePosition != null)
{
itemId = m_browsePosition.ItemId;
}
}
// try to fetch the child.
ComDaBrowseElement child = m_cache.FindChild(session, itemId, targetName);
if (child != null)
{
TraceState("child", child.ItemId, child.BrowseName, child.IsItem, child.HasChildren);
}
if (child == null || (!child.HasChildren && child.IsItem))
{
throw ComUtils.CreateComException(ResultIds.E_INVALIDARG);
}
// update the browse position.
lock (m_lock)
{
m_browsePosition = child;
}
}
/// <summary>
/// Recursively browses for items.
/// </summary>
/// <param name="session">The session.</param>
/// <param name="parent">The parent.</param>
/// <param name="hits">The hits.</param>
private void BrowseForItems(Session session, ComDaBrowseElement parent, List <ComDaBrowseElement> hits)
{
string itemId = String.Empty;
string continuationPoint = null;
if (parent != null)
{
itemId = parent.ItemId;
}
IList <ComDaBrowseElement> elements = m_browseManager.BrowseForElements(
session,
itemId,
null,
0,
(int)BrowseElementFilter.All,
null,
out continuationPoint);
for (int ii = 0; ii < elements.Count; ii++)
{
ComDaBrowseElement element = elements[ii];
if (element.IsHistoricalItem)
{
hits.Add(element);
}
if (element.HasChildren)
{
BrowseForItems(session, element, hits);
}
}
}
/// <summary>
/// Browses the current branch.
/// </summary>
/// <param name="browseType">Type of the browse.</param>
/// <returns>
/// The list of names that meet the criteria.
/// </returns>
public IList <string> Browse(int browseType)
{
Session session = m_server.Session;
if (session == null)
{
throw ComUtils.CreateComException(ResultIds.E_FAIL);
}
string itemId = String.Empty;
string continuationPoint = null;
ComDaBrowseElement position = m_browseManager.GetBrowsePosition(session);
if (position != null)
{
itemId = position.ItemId;
}
IList <ComDaBrowseElement> elements = m_browseManager.BrowseForElements(
session,
itemId,
null,
0,
(int)BrowseElementFilter.All,
null,
out continuationPoint);
return(ApplyFilters(elements, browseType));
}
/// <summary>
/// Browses up.
/// </summary>
/// <param name="session">The session.</param>
public void BrowseUp(Session session)
{
TraceState("BrowseUp");
// find the id of the current node.
string itemId = null;
lock (m_lock)
{
// check if already at root.
if (m_browsePosition == null || String.IsNullOrEmpty(m_browsePosition.ItemId))
{
throw ComUtils.CreateComException(ResultIds.E_FAIL);
}
itemId = m_browsePosition.ItemId;
}
// find the parent - revert to root if parent does not exist.
ComDaBrowseElement parent = m_cache.FindParent(session, itemId);
lock (m_lock)
{
m_browsePosition = parent;
}
}
/// <summary>
/// Gets the item id for the specified browse element.
/// </summary>
/// <param name="session">The session.</param>
/// <param name="browseName">The name of the browse element.</param>
/// <returns>Null if the browseName is not valid for the current position.</returns>
public string GetItemId(Session session, string browseName)
{
TraceState("GetItemId", browseName);
// find the id of the current element.
string itemId = null;
lock (m_lock)
{
if (m_browsePosition != null)
{
itemId = m_browsePosition.ItemId;
}
}
// return the current element.
if (String.IsNullOrEmpty(browseName))
{
return(itemId);
}
// try to fetch the child.
ComDaBrowseElement child = m_cache.FindChild(session, itemId, browseName);
if (child == null)
{
throw ComUtils.CreateComException(ResultIds.E_INVALIDARG);
}
// return child id.
return(child.ItemId);
}
/// <summary>
/// Applies the filters to the list of names.
/// </summary>
/// <param name="elements">The elements.</param>
/// <param name="browseType">Type of the browse.</param>
/// <returns></returns>
private IList <string> ApplyFilters(IList <ComDaBrowseElement> elements, int browseType)
{
List <string> names = new List <string>();
for (int ii = 0; ii < elements.Count; ii++)
{
ComDaBrowseElement element = elements[ii];
if (browseType == (int)OPCHDA_BROWSETYPE.OPCHDA_BRANCH)
{
if (!element.HasChildren)
{
continue;
}
}
if (browseType == (int)OPCHDA_BROWSETYPE.OPCHDA_LEAF)
{
if (!element.IsHistoricalItem || element.HasChildren)
{
continue;
}
}
if (browseType == (int)OPCHDA_BROWSETYPE.OPCHDA_ITEMS)
{
if (!element.IsHistoricalItem)
{
continue;
}
}
if (m_filters != null)
{
for (int jj = 0; jj < m_filters.Count; jj++)
{
if (!MatchFilter(element.BrowseName, m_filters[jj]))
{
continue;
}
}
}
if (browseType == (int)OPCHDA_BROWSETYPE.OPCHDA_ITEMS || browseType == (int)OPCHDA_BROWSETYPE.OPCHDA_FLAT)
{
names.Add(element.ItemId);
}
else
{
names.Add(element.BrowseName);
}
}
return(names);
}
/// <summary>
/// Browse for all items below the current branch.
/// </summary>
/// <returns>
/// The list of item ids that meet the criteria.
/// </returns>
public IList <string> BrowseForItems()
{
Session session = m_server.Session;
if (session == null)
{
throw ComUtils.CreateComException(ResultIds.E_FAIL);
}
ComDaBrowseElement position = m_browseManager.GetBrowsePosition(session);
List <ComDaBrowseElement> elements = new List <ComDaBrowseElement>();
BrowseForItems(session, position, elements);
return(ApplyFilters(elements, (int)OPCHDA_BROWSETYPE.OPCHDA_FLAT));
}
/// <summary>
/// Moves the current browse position to the specified item.
/// </summary>
/// <param name="session">The session.</param>
/// <param name="itemId">The item id.</param>
public void BrowseTo(Session session, string itemId)
{
TraceState("BrowseTo", itemId);
// try to fetch the target.
ComDaBrowseElement target = m_cache.FindElement(session, itemId);
if (target == null)
{
BrowseDown(session, itemId);
return;
}
if (!target.HasChildren)
{
throw ComUtils.CreateComException(ResultIds.E_INVALIDARG);
}
// update the browse position.
lock (m_lock)
{
m_browsePosition = target;
}
}
/// <summary>
/// Browses for the children of the specified item.
/// </summary>
/// <param name="session">The session.</param>
/// <param name="itemId">The item id.</param>
/// <param name="continuationPoint">The continuation point.</param>
/// <param name="maxElementsReturned">The max elements returned.</param>
/// <param name="elementFilter">The element filter.</param>
/// <param name="nameFilter">The name filter.</param>
/// <param name="revisedContinuationPoint">The revised continuation point.</param>
/// <returns>The list of elements that meet the criteria.</returns>
public List <ComDaBrowseElement> BrowseForElements(
Session session,
string itemId,
string continuationPoint,
int maxElementsReturned,
int elementFilter,
string nameFilter,
out string revisedContinuationPoint)
{
TraceState("BrowseForElements", itemId, continuationPoint, maxElementsReturned, elementFilter, nameFilter);
revisedContinuationPoint = String.Empty;
// look up continuation point.
ContinuationPoint cp = null;
if (!String.IsNullOrEmpty(continuationPoint))
{
if (!m_continuationPoints.TryGetValue(continuationPoint, out cp))
{
throw ComUtils.CreateComException(ResultIds.E_INVALIDCONTINUATIONPOINT);
}
m_continuationPoints.Remove(continuationPoint);
}
// get the element queue.
Queue <ComDaBrowseElement> elements = null;
// get element from continuation point.
if (cp != null)
{
elements = cp.Elements;
}
// get list from cache.
else
{
elements = m_cache.BrowseForElements(session, itemId);
// check if nothing found.
if (elements == null)
{
throw ComUtils.CreateComException(ResultIds.E_UNKNOWNITEMID);
}
}
// apply filters.
List <ComDaBrowseElement> hits = new List <ComDaBrowseElement>();
while (elements.Count > 0)
{
ComDaBrowseElement hit = elements.Dequeue();
// apply name filter.
if (!String.IsNullOrEmpty(nameFilter))
{
if (!ComUtils.Match(hit.BrowseName, nameFilter, true))
{
continue;
}
}
// apply element filter
if (elementFilter == (int)OpcRcw.Da.OPCBROWSEFILTER.OPC_BROWSE_FILTER_BRANCHES)
{
if (!hit.HasChildren)
{
continue;
}
}
if (elementFilter == (int)OpcRcw.Da.OPCBROWSEFILTER.OPC_BROWSE_FILTER_ITEMS)
{
if (!hit.IsItem)
{
continue;
}
}
// check max reached.
if (maxElementsReturned > 0 && hits.Count == maxElementsReturned)
{
elements.Enqueue(hit);
cp = new ContinuationPoint();
cp.Id = Guid.NewGuid().ToString();
cp.Elements = elements;
m_continuationPoints.Add(cp.Id, cp);
revisedContinuationPoint = cp.Id;
break;
}
// add the result.
hits.Add(hit);
}
// return results.
return(hits);
}
/// <summary>
/// Recursively browses for items.
/// </summary>
/// <param name="session">The session.</param>
/// <param name="parent">The parent.</param>
/// <param name="hits">The hits.</param>
private void BrowseForItems(Session session, ComDaBrowseElement parent, List<ComDaBrowseElement> hits)
{
string itemId = String.Empty;
string continuationPoint = null;
if (parent != null)
{
itemId = parent.ItemId;
}
IList<ComDaBrowseElement> elements = m_browseManager.BrowseForElements(
session,
itemId,
null,
0,
(int)BrowseElementFilter.All,
null,
out continuationPoint);
for (int ii = 0; ii < elements.Count; ii++)
{
ComDaBrowseElement element = elements[ii];
if (element.IsHistoricalItem)
{
hits.Add(element);
}
if (element.HasChildren)
{
BrowseForItems(session, element, hits);
}
}
}
