using Opc.Ua; // create an object node id with an integer identifier NodeId objectId = new NodeId(1234); // create a qualified name node id with a string identifier and namespace index NodeId qualifiedNameId = new NodeId("ServerStatus", 2); // create a string node id with a URI-based identifier NodeId stringNodeId = new NodeId("http://example.com/myobject", 1);In this example, we create three different NodeId objects using different constructor overloads. The first NodeId uses an integer identifier, while the second uses a string identifier and namespace index. The third NodeId uses a URI-based identifier. The Opc.Ua.Core library provides a set of classes and interfaces for implementing OPC UA servers and clients. It includes functionality for encoding and decoding messages, managing sessions, and browsing the server's namespace. Overall, it provides a complete set of tools for building robust OPC UA applications in C#.