/// <summary>
/// Fetches the set of data filters from the server.
/// </summary>
/// <param name="server">The server object</param>
public TsCCpxComplexItem[] GetDataFilters(TsCDaServer server)
{
// not a valid operation for data filter items.
if (_unfilteredItemID != null)
{
return(null);
}
// data filters not supported by the item.
if (_filterItem == null)
{
return(null);
}
TsCDaBrowsePosition position = null;
try
{
// browse any existing filter instances.
TsCDaBrowseFilters filters = new TsCDaBrowseFilters {
ElementNameFilter = null, BrowseFilter = TsCDaBrowseFilter.Item, ReturnAllProperties = false, PropertyIDs = CPX_PROPERTIES, ReturnPropertyValues = true
};
TsCDaBrowseElement[] elements = server.Browse(_filterItem, filters, out position);
// nothing found.
if (elements == null || elements.Length == 0)
{
return(new TsCCpxComplexItem[0]);
}
// contruct an array of complex data items for each available data filter.
ArrayList dataFilters = new ArrayList(elements.Length);
Array.ForEach(elements, element =>
{
TsCCpxComplexItem item = new TsCCpxComplexItem();
if (item.Init(element))
{
dataFilters.Add(item);
}
});
// return the set of available data filters.
return((TsCCpxComplexItem[])dataFilters.ToArray(typeof(TsCCpxComplexItem)));
}
finally
{
if (position != null)
{
position.Dispose();
position = null;
}
}
}
/// <summary>
/// Fetches the item id for the data filters items and stores it in the internal cache.
/// </summary>
/// <param name="server">The server object</param>
public void GetDataFilterItem(TsCDaServer server)
{
_filterItem = null;
// not a valid operation for data filter items.
if (_unfilteredItemID != null)
{
return;
}
TsCDaBrowsePosition position = null;
try
{
OpcItem itemID = new OpcItem(this);
// browse any existing filter instances.
TsCDaBrowseFilters filters = new TsCDaBrowseFilters {
ElementNameFilter = CPX_DATA_FILTERS, BrowseFilter = TsCDaBrowseFilter.All, ReturnAllProperties = false, PropertyIDs = null, ReturnPropertyValues = false
};
TsCDaBrowseElement[] elements = null;
// browse for the 'CPX' branch first.
if (_unconvertedItemID == null)
{
filters.ElementNameFilter = CPX_BRANCH;
elements = server.Browse(itemID, filters, out position);
// nothing found.
if (elements == null || elements.Length == 0)
{
return;
}
// release the position object.
if (position != null)
{
position.Dispose();
position = null;
}
// update the item for the next browse operation.
itemID = new OpcItem(elements[0].ItemPath, elements[0].ItemName);
filters.ElementNameFilter = CPX_DATA_FILTERS;
}
// browse for the 'DataFilters' branch.
elements = server.Browse(itemID, filters, out position);
// nothing found.
if (elements == null || elements.Length == 0)
{
return;
}
_filterItem = new OpcItem(elements[0].ItemPath, elements[0].ItemName);
}
finally
{
if (position != null)
{
position.Dispose();
position = null;
}
}
}
/// <summary>
/// Creates a new data filter.
/// </summary>
/// <param name="server">The server object</param>
/// <param name="filterName">The name of the filter</param>
/// <param name="filterValue">The value of the filter</param>
public TsCCpxComplexItem CreateDataFilter(TsCDaServer server, string filterName, string filterValue)
{
// not a valid operation for data filter items.
if (_unfilteredItemID != null)
{
return(null);
}
// data filters not supported by the item.
if (_filterItem == null)
{
return(null);
}
TsCDaBrowsePosition position = null;
try
{
// write the desired filter to the server.
TsCDaItemValue item = new TsCDaItemValue(_filterItem);
// create the filter parameters document.
using (StringWriter ostrm = new StringWriter())
{
using (XmlTextWriter writer = new XmlTextWriter(ostrm))
{
writer.WriteStartElement("DataFilters");
writer.WriteAttributeString("Name", filterName);
writer.WriteString(filterValue);
writer.WriteEndElement();
writer.Close();
}
// create the value to write.
item.Value = ostrm.ToString();
}
item.Quality = TsCDaQuality.Bad;
item.QualitySpecified = false;
item.Timestamp = DateTime.MinValue;
item.TimestampSpecified = false;
// write the value.
OpcItemResult[] result = server.Write(new TsCDaItemValue[] { item });
if (result == null || result.Length == 0)
{
throw new OpcResultException(new OpcResult((int)OpcResult.E_FAIL.Code, OpcResult.FuncCallType.SysFuncCall, null), "Unexpected results returned from server.");
}
if (result[0].Result.Failed())
{
throw new OpcResultException(new OpcResult((int)OpcResult.Cpx.E_FILTER_ERROR.Code, OpcResult.FuncCallType.SysFuncCall, null), "Could not create new data filter.");
}
// browse for new data filter item.
TsCDaBrowseFilters filters = new TsCDaBrowseFilters {
ElementNameFilter = filterName, BrowseFilter = TsCDaBrowseFilter.Item, ReturnAllProperties = false, PropertyIDs = CPX_PROPERTIES, ReturnPropertyValues = true
};
TsCDaBrowseElement[] elements = server.Browse(_filterItem, filters, out position);
// nothing found.
if (elements == null || elements.Length == 0)
{
throw new OpcResultException(new OpcResult((int)OpcResult.Cpx.E_FILTER_ERROR.Code, OpcResult.FuncCallType.SysFuncCall, null), "Could not browse to new data filter.");
}
TsCCpxComplexItem filterItem = new TsCCpxComplexItem();
if (!filterItem.Init(elements[0]))
{
throw new OpcResultException(new OpcResult((int)OpcResult.Cpx.E_FILTER_ERROR.Code, OpcResult.FuncCallType.SysFuncCall, null), "Could not initialize to new data filter.");
}
// return the new data filter.
return(filterItem);
}
finally
{
if (position != null)
{
position.Dispose();
position = null;
}
}
}
/// <summary>
/// Fetches the set of type conversions from the server.
/// </summary>
/// <param name="server">The server object</param>
public TsCCpxComplexItem[] GetTypeConversions(TsCDaServer server)
{
// only the root item can have type conversions.
if (_unconvertedItemID != null || _unfilteredItemID != null)
{
return(null);
}
TsCDaBrowsePosition position = null;
try
{
// look for the 'CPX' branch.
TsCDaBrowseFilters filters = new TsCDaBrowseFilters {
ElementNameFilter = CPX_BRANCH, BrowseFilter = TsCDaBrowseFilter.Branch, ReturnAllProperties = false, PropertyIDs = null, ReturnPropertyValues = false
};
TsCDaBrowseElement[] elements = server.Browse(this, filters, out position);
// nothing found.
if (elements == null || elements.Length == 0)
{
return(null);
}
// release the browse position object.
if (position != null)
{
position.Dispose();
position = null;
}
// browse for type conversions.
OpcItem itemID = new OpcItem(elements[0].ItemPath, elements[0].ItemName);
filters.ElementNameFilter = null;
filters.BrowseFilter = TsCDaBrowseFilter.Item;
filters.ReturnAllProperties = false;
filters.PropertyIDs = CPX_PROPERTIES;
filters.ReturnPropertyValues = true;
elements = server.Browse(itemID, filters, out position);
// nothing found.
if (elements == null || elements.Length == 0)
{
return(new TsCCpxComplexItem[0]);
}
// contruct an array of complex data items for each available conversion.
ArrayList conversions = new ArrayList(elements.Length);
Array.ForEach(elements, element =>
{
if (element.Name != CPX_DATA_FILTERS)
{
TsCCpxComplexItem item = new TsCCpxComplexItem();
if (item.Init(element))
{
// check if data filters supported for type conversion.
item.GetDataFilterItem(server);
conversions.Add(item);
}
}
});
// return the set of available conversions.
return((TsCCpxComplexItem[])conversions.ToArray(typeof(TsCCpxComplexItem)));
}
finally
{
if (position != null)
{
position.Dispose();
position = null;
}
}
}