public virtual BrowseElement[] BrowseNext(ref Opc.Da.BrowsePosition position)
{
lock (this)
{
if (base.m_server == null)
{
throw new NotConnectedException();
}
if ((position == null) || (position.GetType() != typeof(OpcCom.Da.BrowsePosition)))
{
throw new BrowseCannotContinueException();
}
OpcCom.Da.BrowsePosition position2 = (OpcCom.Da.BrowsePosition)position;
if (((position2 == null) || (position2.ContinuationPoint == null)) || (position2.ContinuationPoint == ""))
{
throw new BrowseCannotContinueException();
}
int pdwCount = 0;
int pbMoreElements = 0;
ItemIdentifier itemID = ((OpcCom.Da.BrowsePosition)position).ItemID;
BrowseFilters filters = ((OpcCom.Da.BrowsePosition)position).Filters;
IntPtr pszContinuationPoint = Marshal.StringToCoTaskMemUni(position2.ContinuationPoint);
IntPtr zero = IntPtr.Zero;
try
{
((IOPCBrowse)base.m_server).Browse(((itemID != null) && (itemID.ItemName != null)) ? itemID.ItemName : "", ref pszContinuationPoint, filters.MaxElementsReturned, OpcCom.Da.Interop.GetBrowseFilter(filters.BrowseFilter), (filters.ElementNameFilter != null) ? filters.ElementNameFilter : "", (filters.VendorFilter != null) ? filters.VendorFilter : "", filters.ReturnAllProperties ? 1 : 0, filters.ReturnPropertyValues ? 1 : 0, (filters.PropertyIDs != null) ? filters.PropertyIDs.Length : 0, OpcCom.Da.Interop.GetPropertyIDs(filters.PropertyIDs), out pbMoreElements, out pdwCount, out zero);
}
catch (Exception exception)
{
throw OpcCom.Interop.CreateException("IOPCBrowse.BrowseNext", exception);
}
BrowseElement[] elements = OpcCom.Da.Interop.GetBrowseElements(ref zero, pdwCount, true);
position2.ContinuationPoint = Marshal.PtrToStringUni(pszContinuationPoint);
Marshal.FreeCoTaskMem(pszContinuationPoint);
if ((pbMoreElements == 0) && ((position2.ContinuationPoint == null) || (position2.ContinuationPoint == "")))
{
position = null;
}
this.ProcessResults(elements, filters.PropertyIDs);
return(elements);
}
}
public virtual BrowseElement[] Browse(ItemIdentifier itemID, BrowseFilters filters, out Opc.Da.BrowsePosition position)
{
if (filters == null)
{
throw new ArgumentNullException("filters");
}
lock (this)
{
if (base.m_server == null)
{
throw new NotConnectedException();
}
position = null;
int pdwCount = 0;
int pbMoreElements = 0;
IntPtr zero = IntPtr.Zero;
IntPtr ppBrowseElements = IntPtr.Zero;
try
{
((IOPCBrowse)base.m_server).Browse(((itemID != null) && (itemID.ItemName != null)) ? itemID.ItemName : "", ref zero, filters.MaxElementsReturned, OpcCom.Da.Interop.GetBrowseFilter(filters.BrowseFilter), (filters.ElementNameFilter != null) ? filters.ElementNameFilter : "", (filters.VendorFilter != null) ? filters.VendorFilter : "", filters.ReturnAllProperties ? 1 : 0, filters.ReturnPropertyValues ? 1 : 0, (filters.PropertyIDs != null) ? filters.PropertyIDs.Length : 0, OpcCom.Da.Interop.GetPropertyIDs(filters.PropertyIDs), out pbMoreElements, out pdwCount, out ppBrowseElements);
}
catch (Exception exception)
{
throw OpcCom.Interop.CreateException("IOPCBrowse.Browse", exception);
}
BrowseElement[] elements = OpcCom.Da.Interop.GetBrowseElements(ref ppBrowseElements, pdwCount, true);
string continuationPoint = Marshal.PtrToStringUni(zero);
Marshal.FreeCoTaskMem(zero);
if ((pbMoreElements != 0) || ((continuationPoint != null) && (continuationPoint != "")))
{
position = new OpcCom.Da.BrowsePosition(itemID, filters, continuationPoint);
}
this.ProcessResults(elements, filters.PropertyIDs);
return(elements);
}
}
//======================================================================
// BrowseNext
/// <summary>
/// Continues a browse operation with previously specified search criteria.
/// </summary>
/// <param name="position">An object containing the browse operation state information.</param>
/// <returns>The set of elements found.</returns>
public virtual BrowseElement[] BrowseNext(ref Opc.Da.BrowsePosition position)
{
lock (this)
{
if (m_server == null)
{
throw new NotConnectedException();
}
// check for valid position object.
if (position == null || position.GetType() != typeof(OpcCom.Da.BrowsePosition))
{
throw new BrowseCannotContinueException();
}
OpcCom.Da.BrowsePosition pos = (OpcCom.Da.BrowsePosition)position;
// check for valid continuation point.
if (pos == null || pos.ContinuationPoint == null || pos.ContinuationPoint == "")
{
throw new BrowseCannotContinueException();
}
// initialize arguments.
int count = 0;
int moreElements = 0;
ItemIdentifier itemID = ((BrowsePosition)position).ItemID;
BrowseFilters filters = ((BrowsePosition)position).Filters;
IntPtr pContinuationPoint = Marshal.StringToCoTaskMemUni(pos.ContinuationPoint);
IntPtr pElements = IntPtr.Zero;
// invoke COM method.
try
{
((IOPCBrowse)m_server).Browse(
(itemID != null && itemID.ItemName != null)?itemID.ItemName:"",
ref pContinuationPoint,
filters.MaxElementsReturned,
OpcCom.Da.Interop.GetBrowseFilter(filters.BrowseFilter),
(filters.ElementNameFilter != null)?filters.ElementNameFilter:"",
(filters.VendorFilter != null)?filters.VendorFilter:"",
(filters.ReturnAllProperties)?1:0,
(filters.ReturnPropertyValues)?1:0,
(filters.PropertyIDs != null)?filters.PropertyIDs.Length:0,
OpcCom.Da.Interop.GetPropertyIDs(filters.PropertyIDs),
out moreElements,
out count,
out pElements);
}
catch (Exception e)
{
throw OpcCom.Interop.CreateException("IOPCBrowse.BrowseNext", e);
}
// unmarshal results.
BrowseElement[] elements = OpcCom.Da.Interop.GetBrowseElements(ref pElements, count, true);
pos.ContinuationPoint = Marshal.PtrToStringUni(pContinuationPoint);
Marshal.FreeCoTaskMem(pContinuationPoint);
// check if more no results exist.
if (moreElements == 0 && (pos.ContinuationPoint == null || pos.ContinuationPoint == ""))
{
position = null;
}
// process results.
ProcessResults(elements, filters.PropertyIDs);
return(elements);
}
}
//======================================================================
// Browse
/// <summary>
/// Fetches the children of a branch that meet the filter criteria.
/// </summary>
/// <param name="itemID">The identifier of branch which is the target of the search.</param>
/// <param name="filters">The filters to use to limit the set of child elements returned.</param>
/// <param name="position">An object used to continue a browse that could not be completed.</param>
/// <returns>The set of elements found.</returns>
public virtual BrowseElement[] Browse(
ItemIdentifier itemID,
BrowseFilters filters,
out Opc.Da.BrowsePosition position)
{
if (filters == null)
{
throw new ArgumentNullException("filters");
}
lock (this)
{
if (m_server == null)
{
throw new NotConnectedException();
}
position = null;
// initialize arguments.
int count = 0;
int moreElements = 0;
IntPtr pContinuationPoint = IntPtr.Zero;
IntPtr pElements = IntPtr.Zero;
// invoke COM method.
try
{
((IOPCBrowse)m_server).Browse(
(itemID != null && itemID.ItemName != null)?itemID.ItemName:"",
ref pContinuationPoint,
filters.MaxElementsReturned,
OpcCom.Da.Interop.GetBrowseFilter(filters.BrowseFilter),
(filters.ElementNameFilter != null)?filters.ElementNameFilter:"",
(filters.VendorFilter != null)?filters.VendorFilter:"",
(filters.ReturnAllProperties)?1:0,
(filters.ReturnPropertyValues)?1:0,
(filters.PropertyIDs != null)?filters.PropertyIDs.Length:0,
OpcCom.Da.Interop.GetPropertyIDs(filters.PropertyIDs),
out moreElements,
out count,
out pElements);
}
catch (Exception e)
{
throw OpcCom.Interop.CreateException("IOPCBrowse.Browse", e);
}
// unmarshal results.
BrowseElement[] elements = OpcCom.Da.Interop.GetBrowseElements(ref pElements, count, true);
string continuationPoint = Marshal.PtrToStringUni(pContinuationPoint);
Marshal.FreeCoTaskMem(pContinuationPoint);
// check if more results exist.
if (moreElements != 0 || (continuationPoint != null && continuationPoint != ""))
{
// allocate new browse position object.
position = new OpcCom.Da.BrowsePosition(itemID, filters, continuationPoint);
}
// process results.
ProcessResults(elements, filters.PropertyIDs);
return(elements);
}
}
