JsonEncoder not correctly closing JSON for ExpandedNodeId - missing curly bracket

[htbmw]

Type of issue

• Bug
• Enhancement
• Compliance
• Question
• Help wanted

Current Behavior

While using the JsonEncoder to serialize event fields, I observed during testing that the final JSON was malformed.
On closer inspection it was found that the ExpandedNodeId is always missing a closing curly bracket when json encoded.

Here are examples of the incorrect string produced by JsonEndode for an ExpandedNodeId:

Single ExpandedNodeId as a JSON object: ending curly bracket is missing

{"field1":{"IdType":1,"Id":"StringIdentifier","Namespace":2}

Multiple ExpandedNodeIds as a JSON object: several curly brackets missing and leads to incorrect nesting

{"field4":{"IdType":1,"Id":"StringIdentifier","Namespace":2,"field5":{"IdType":1,"Id":"StringIdentifier","Namespace":2,"field6":{"IdType":1,"Id":"StringIdentifier","Namespace":2}

Expected Behavior

The correct JSON should look like

Single ExpandedNodeId:
{"field1":{"IdType":1,"Id":"StringIdentifier","Namespace":2}}

Multiple ExpandedNodeIds:
{"field4":{"IdType":1,"Id":"StringIdentifier","Namespace":2},"field5":{"IdType":1,"Id":"StringIdentifier","Namespace":2},"field6":{"IdType":1,"Id":"StringIdentifier","Namespace":2}}

Steps To Reproduce

Run the following code:
Different use cases have been included to see if something would work, eg wrapping the ExpandedNodeId in a variant, passing in the raw ExpandedNodeId without wrapping, calling the WriteExpandedNodeId instead of WriteVariant, but all yield the same incorrect result.

using Opc.Ua;

namespace OpcUaConsoleApp
{
    class Program
    {
        private static async Task Main(string[] args)
        {
            var expandedNodeId = new ExpandedNodeId(new NodeId("ns=2;s=StringIdentifier"),null,23);

            var encoder = new JsonEncoder(ServiceMessageContext.GlobalContext, false);
            encoder.WriteVariant("field1", expandedNodeId);            
            var s = encoder.CloseAndReturnText();
            Console.WriteLine(s);

            var encoder2 = new JsonEncoder(ServiceMessageContext.GlobalContext, false);
            encoder2.WriteVariant("field2", new Variant(expandedNodeId));            
            var s2 = encoder2.CloseAndReturnText();
            Console.WriteLine(s2);

            var encoder3 = new JsonEncoder(ServiceMessageContext.GlobalContext, false);
            encoder3.WriteExpandedNodeId("field3", expandedNodeId);
            var s3 = encoder3.CloseAndReturnText();
            Console.WriteLine(s3);

            var encoder4 = new JsonEncoder(ServiceMessageContext.GlobalContext, false);
            encoder4.WriteVariant("field4", expandedNodeId);
            encoder4.WriteVariant("field5", new Variant(expandedNodeId));
            encoder4.WriteExpandedNodeId("field6", expandedNodeId);
            var s4 = encoder4.CloseAndReturnText();
            Console.WriteLine(s4);
        }
    }
}

Environment

- OS: Any
- Environment: Any
- Runtime: dotnet9
- Nuget Version: Any, including latest
- Component: JsonEncoder
- Server:
- Client:

Anything else?

No response