/// <summary>
/// Fetches the subtypes for the node.
/// </summary>
private List<ReferenceDescription> BrowseSubTypes(Opc.Ua.Client.Session client, NodeId nodeId)
{
List<ReferenceDescription> references = new List<ReferenceDescription>();
// specify the references to follow and the fields to return.
BrowseDescription nodeToBrowse = new BrowseDescription();
nodeToBrowse.NodeId = nodeId;
nodeToBrowse.ReferenceTypeId = ReferenceTypeIds.HasSubtype;
nodeToBrowse.IncludeSubtypes = true;
nodeToBrowse.BrowseDirection = BrowseDirection.Forward;
nodeToBrowse.NodeClassMask = 0;
nodeToBrowse.ResultMask = (uint)BrowseResultMask.All;
BrowseDescriptionCollection nodesToBrowse = new BrowseDescriptionCollection();
nodesToBrowse.Add(nodeToBrowse);
// start the browse operation.
BrowseResultCollection results = null;
DiagnosticInfoCollection diagnosticInfos = null;
ResponseHeader responseHeader = client.Browse(
null,
null,
0,
nodesToBrowse,
out results,
out diagnosticInfos);
// these do sanity checks on the result - make sure response matched the request.
ClientBase.ValidateResponse(results, nodesToBrowse);
ClientBase.ValidateDiagnosticInfos(diagnosticInfos, nodesToBrowse);
// check status.
if (StatusCode.IsBad(results[0].StatusCode))
{
// embed the diagnostic information in a exception.
throw ServiceResultException.Create(results[0].StatusCode, 0, diagnosticInfos, responseHeader.StringTable);
}
// add first batch.
references.AddRange(results[0].References);
// check if server limited the results.
while (results[0].ContinuationPoint != null && results[0].ContinuationPoint.Length > 0)
{
ByteStringCollection continuationPoints = new ByteStringCollection();
continuationPoints.Add(results[0].ContinuationPoint);
// continue browse operation.
responseHeader = client.BrowseNext(
null,
false,
continuationPoints,
out results,
out diagnosticInfos);
ClientBase.ValidateResponse(results, continuationPoints);
ClientBase.ValidateDiagnosticInfos(diagnosticInfos, continuationPoints);
// check status.
if (StatusCode.IsBad(results[0].StatusCode))
{
// embed the diagnostic information in a exception.
throw ServiceResultException.Create(results[0].StatusCode, 0, diagnosticInfos, responseHeader.StringTable);
}
// add next batch.
references.AddRange(results[0].References);
}
return references;
}
