Method call for custom complex types.|OPC UA Implementation: Stacks, Tools, and Samples|Forum|OPC Foundation

Randy Armstrong said
The C# API takes an Object but complex types must be wrapped in an ExtensionObject.

Any type that implements the IEncodeable interface can be placed in an ExtensionObject.

  

Thanks for your feedback. I’ve taken another attempt but I’m still having problems.

Here is my new code for making the method call:

NodeId node = (NodeId)objectReference.NodeId;
NodeId method = (NodeId)methodReference.NodeId;

EncodeableFactory.GlobalFactory.AddEncodeableType(typeof(ST_ClientTEST02));
ST_ClientTEST02 v1 = new ST_ClientTEST02();
v1.Distance = 1;
v1.Duration = 1;
v1.Status = 1;

var result = m_s.Call(node, method, new ExtensionObject(v1));

I am getting an invalid argument error.

This is the IEncodable class I’ve created: 

public class ST_ClientTEST02 : EncodeableObject
{
public UInt32 Distance { get; set; }
public UInt32 Duration { get; set; }
public UInt32 Status { get; set; }

public override ExpandedNodeId TypeId
{
get { return ExpandedNodeId.Parse(“ns=6;i=100170”); }
//protected set { _myProp = value; }
}

public override ExpandedNodeId BinaryEncodingId
{
get { return ExpandedNodeId.Parse(“ns=6;i=100175”); }
}

public override ExpandedNodeId XmlEncodingId
{
get { return null; }
}

public override void Encode(IEncoder encoder)
{
encoder.WriteUInt32(“Distance”, this.Distance);
encoder.WriteUInt32(“Duration”, this.Duration);
encoder.WriteUInt32(“Status”, this.Status);
}

public override void Decode(IDecoder decoder)
{
this.Distance = decoder.ReadUInt32(“Distance”);
this.Duration = decoder.ReadUInt32(“Duration”);
this.Status = decoder.ReadUInt32(“Status”);
}

public override string ToString()
{
return “{distance=” + this.Distance.ToString() + “; Duration=” + Duration.ToString() + “; status=” + this.Status.ToString() + “}”;
}
}

Any pointers?

Thanks for you feedback. 

I’ve  been trying to get this working with the correct uri/nsu, but I can’t get it working. I’ve only been using the index previously and am not sure I’m formatting the uri correctly. Is there a way of translating from index to nsu/uri to make sure I’ve got the correct uri/nsu? I can’t seem to find a way of getting this.

Thanks for replying Randy.

I’m aware of what the IEncodable passed in will do. Whatever I try I can’t get the TypeId or BinaryEncoding Id correct.

I’m taking a step back and trying to verify I can get the URI address correct and read a node through the session.ReadNode 

As I say I’m a complete novice at this so may be making simple basic errors, but I hitting brick walls I can’t find answers to so I’m completely stuck.

Code snippet of what I’m trying to do.

string id = “”;

// i can read this node ok
id = “ns=6;i=100055”;
var val1 = m_s.ReadNode(NodeId.Parse(id));

//Contents of server namespace array property
//[0] https://opcfoundation.org/UA/
//[1] urn:br-automation/BR/UA/EmbeddedServer
//[2] https://opcfoundation.org/UA/DI/
//[3] http://PLCopen.org/OpcUa/IEC61131-3/
//[4] http://br-automation.com/OpcUa/PLC/
//[5]
//[6] http://br-automation.com/OpcUa/PLC/PV/

// I’m trying to veryify a URI/NSU method of reading the node, then I can veryify I at least have the address correct.
// This does not work – Bad Id.
id = “http://br-automation.com/OpcUa/PLC/;i=100055”;
NodeId nid = NodeId.Parse(id);    // I’m assuming this can take a URI? If not how can I read a node using the URI?
var val2 = m_s.ReadNode(nid);

Thank you very much. I have it working now.

I found it tricky to know precisely how to use the Extension Object. I couldn’t find any detailed documentation – even  a list of the properties and methods on the ExtensionObject class. Can anyone point me to any documentation?

I ended up either looking at the code for the ExtensionObject Class in GitHub or using wireshark to see how UA expert formulated the messages. 

Thanks for all the help on this thread. It’s been a huge help to a newbie like me.