OPC-UA_Client

An easier way to access an OPC-UA Server. This acts as an Add-On for the standard OPC-UA Library, not a completely new one.

Installation

• Add a reference to
  • Microsoft.Extensions.Logging.Abstractions.dll
  • Newtonsoft.Json.dll
  • Opc.Ua.Client.dll
  • Opc.Ua.Configuration.dll
  • Opc.Ua.Core.dll
  • Opc.Ua.Security.Certificates.dll
  • System.Diagnostics.DiagnosticSource.dll
  • System.Formats.Asn1.dll
  • System.Runtime.CompilerServices.Unsafe.dll
  • System.Security.Cryptography.Cng.dll
  • OPC-UA_Client.dll
• If you have the OPC-UA standard lib installed, you just need to reference the last dll
• Add a using directive: using Opc.Ua.CustomClient;

Library Content

Client

• Client(string serverEndpoint): Creates a Client Instance that automatically connects itself to the specified OPC-UA Server.
• ServerObject GetObjectByName(string name): Gets a ServerObject by its Name.
• ServerObject GetObjectByNodeId(string nodeId): Gets a ServerObject by its Node Id.
• ServerObject[] GetObjects(): Gets all ServerObjects.
• ServerObject[] GetObjects(int typeIdFilter): Gets all ServerObjects that have the specified Type Id.
• Session GetSession(): Gets the current OPC-UA Session for accessing the Client with the standard OPC-UA Library.
• bool IsConnected(): Returns true if the Client is currently connected to the OPC-UA Server.
• bool NameExists(string name): Returns true if an Object with the specified Name exists.
• bool NodeIdExists(string nodeId): Returns true if an Object with the specified Node Id exists.
• bool NameExistsInObject(string name, ServerObject obj): Returns true if an Object with the specified Name exists in the ServerObject.
• bool NodeIdExistsInObject(string nodeId, ServerObject obj): Returns true if an Object with the specified Node Id exists in the ServerObject.
• void Refresh(): Refreshes the Connection to the OPC-UA Server. This should be used after creating new Objects with the Client.
• void RefreshObjects(): Refreshes the Objects in the Client without refreshing the Connection.
• void RefreshChildObjects(ServerObject obj): Refreshes the Child Objects of the specified Object.

ServerObject

• ReferenceDescription GetHandle(): Gets the ReferenceDescription of the Object to access it with the standard OPC-UA Library.
• int GetTypeId(): Gets the Type of the Object as an Integer. The Type Ids can be found in the Model.csv File of the OPC-UA Server.
• ServerObject GetParent(): Gets the Parent Object that contains the current one.
• string GetNodeId(): Gets the Node Id of the current Object.
• MethodDescription Method(string name): Gets the MethodDescription of the Method with the specified Name to call it.
• VariableDescription Variable(string name): Gets the VariableDescription of the Variable with the specified Name to get or set its value.

MethodDescription

• MethodDescription(ReferenceDescription desc, ServerObject parent, Session session): Converts a ReferenceDescription to a MethodDescription.
• IList<object> Call(params object[] args): Calls the Method with the specified Arguments and returns one or multiple return Values.

VariableDescription

• VariableDescription(ReferenceDescription desc, Session session): Converts a ReferenceDescription to a VariableDescription.
• T Get<T>(): Gets the Value of the Variable with the specified Type.
• void Set<T>(T value): Sets the Value of the Variable with the specified Type.

Examples

//Create a client which connects to the given server address
Client cli = new Client("opc.tcp://localhost:1337/");
//Get all objects of a specific type
ServerObject[] objects = cli.GetObjects(69);
//Check if a name exists
bool nameExists = cli.NameExists("myObject1");
//Check if a node id exists
bool nodeExists = cli.NodeIdExists("myNodeId1");
//Get an object by its name
ServerObject myObject1 = cli.GetObjectByName("myObject1");
//Call a method by its name in the object
IList<object> returnValue = myObject1.Method("CreateChildObject").Call("myObject2", 420u);
//Refresh the client's data to display the new object
cli.Refresh();
//Get an object by its node id
ServerObject myObject2 = cli.GetObjectByNodeId("myObject1-myObject2");
//Get a variable from an object by its name
VariableDescription id = myObject2.Variable("ObjectId");
//Get the value of the variable
uint oldValue = id.Get<uint>();
//Set the value of the variable
CellNumber.Set<uint>(69u);
//Get the updated value of the variable
uint newValue = id.Get<uint>();