public void QueryAvailableProperties(string itemId)
{
var pdwCount = 0;
var ppPropertyIds = IntPtr.Zero;
var ppDescriptions = IntPtr.Zero;
var ppvtDataTypes = IntPtr.Zero;
_server.QueryAvailableProperties(itemId, out pdwCount, out ppPropertyIds, out ppDescriptions, out ppvtDataTypes);
if (pdwCount > 0)
{
var ids = ComUtils.GetInt32s(ref ppPropertyIds, pdwCount, true);
var descs = ComUtils.GetUnicodeStrings(ref ppDescriptions, pdwCount, true);
var types = ComUtils.GetInt16s(ref ppvtDataTypes, pdwCount, true);
}
}
/// <summary>
/// Gets the event attributes.
/// </summary>
/// <param name="categoryId">The category id.</param>
/// <param name="attributeIds">The attribute ids.</param>
/// <param name="descriptions">The descriptions.</param>
/// <param name="datatypes">The datatypes.</param>
public bool GetEventAttributes(
int categoryId,
out int[] attributeIds,
out string[] descriptions,
out short[] datatypes)
{
string methodName = "IOPCEventServer.QueryEventAttributes";
int count = 0;
IntPtr pAttributeIds = IntPtr.Zero;
IntPtr pDescriptions = IntPtr.Zero;
IntPtr pDataTypes = IntPtr.Zero;
try
{
IOPCEventServer server = BeginComCall <IOPCEventServer>(methodName, true);
server.QueryEventAttributes(
categoryId,
out count,
out pAttributeIds,
out pDescriptions,
out pDataTypes);
}
catch (Exception e)
{
ComCallError(methodName, e);
}
finally
{
EndComCall(methodName);
}
// unmarshal results.
attributeIds = ComUtils.GetInt32s(ref pAttributeIds, count, true);
descriptions = ComUtils.GetUnicodeStrings(ref pDescriptions, count, true);
datatypes = ComUtils.GetInt16s(ref pDataTypes, count, true);
// remove the AREAS attribute which is never exposed.
for (int ii = 0; ii < count; ii++)
{
if (String.Compare(descriptions[ii], "AREAS", StringComparison.OrdinalIgnoreCase) == 0)
{
int[] attributeIds2 = new int[count - 1];
string[] descriptions2 = new string[count - 1];
short[] datatypes2 = new short[count - 1];
if (ii > 0)
{
Array.Copy(attributeIds, attributeIds2, ii);
Array.Copy(descriptions, descriptions2, ii);
Array.Copy(datatypes, datatypes2, ii);
}
if (ii < count - 1)
{
Array.Copy(attributeIds, ii + 1, attributeIds2, ii, count - ii - 1);
Array.Copy(descriptions, ii + 1, descriptions2, ii, count - ii - 1);
Array.Copy(datatypes, ii + 1, datatypes2, ii, count - ii - 1);
}
attributeIds = attributeIds2;
descriptions = descriptions2;
datatypes = datatypes2;
break;
}
}
return(count > 0);
}
/// <summary>
/// Read the available non-built in properties from the server.
/// </summary>
/// <param name="itemId">The item id.</param>
/// <param name="updateCache">if set to <c>true</c> the cache is updated.</param>
/// <returns>The array of properties.</returns>
public DaProperty[] ReadAvailableProperties(string itemId, bool updateCache)
{
string methodName = "IOPCItemProperties.QueryAvailableProperties";
// query for available properties.
int count = 0;
IntPtr pPropertyIds = IntPtr.Zero;
IntPtr pDescriptions = IntPtr.Zero;
IntPtr pDataTypes = IntPtr.Zero;
try
{
IOPCItemProperties server = BeginComCall <IOPCItemProperties>(methodName, true);
server.QueryAvailableProperties(
itemId,
out count,
out pPropertyIds,
out pDescriptions,
out pDataTypes);
}
catch (Exception e)
{
if (ComUtils.IsUnknownError(e, ResultIds.E_FAIL, ResultIds.E_UNKNOWNITEMID, ResultIds.E_INVALIDITEMID))
{
ComUtils.TraceComError(e, methodName);
}
return(null);
}
finally
{
EndComCall(methodName);
}
// unmarshal results.
int[] propertyIds = ComUtils.GetInt32s(ref pPropertyIds, count, true);
string[] descriptions = ComUtils.GetUnicodeStrings(ref pDescriptions, count, true);
short[] datatype = ComUtils.GetInt16s(ref pDataTypes, count, true);
List <DaProperty> properties = new List <DaProperty>();
for (int ii = 0; ii < count; ii++)
{
// do not return any of the built in properties.
if (propertyIds[ii] <= PropertyIds.TimeZone)
{
continue;
}
DaProperty property = new DaProperty();
property.PropertyId = propertyIds[ii];
property.Name = descriptions[ii];
property.DataType = datatype[ii];
properties.Add(property);
}
// fetch the item ids.
if (properties.Count > 0)
{
DaProperty[] array = properties.ToArray();
GetPropertyItemIds(itemId, array);
// update the cache.
if (updateCache)
{
lock (m_cache)
{
DaElement element = null;
if (m_cache.TryGetValue(itemId, out element))
{
element.Properties = array;
}
}
}
return(array);
}
return(null);
}