IOpcNode Members

Namespace: Opc.UaFx
Assemblies: Opc.UaFx.Advanced.dll, Opc.UaFx.Advanced.dll
The IOpcNode interface defines the following members.

Description

Gets or sets the value of the optional DescriptionOpcAttribute which shall explain the meaning of the node.

C#

OpcText Description { get; set; }


Property Value

OpcText

A localizable instance of the OpcText class which optionally explains the meaning of the node or a null reference (Nothing in Visual Basic) if there is no description associated with the node.



Remarks

The menaning of the node defines the usage, the context and the purpose of the node.

DisplayName

Gets or sets the value of the DisplayNameOpcAttribute which defines the localizable name of the node.

C#

OpcText DisplayName { get; set; }


Property Value

OpcText

An instance of the OpcText class which defines the localizable name of the node.



Remarks

Client application should use this attribute if they want to display the name of the node to the user. The String part of the DisplayName is restricted to 512 characters.

HasPendingChanges

C#

bool HasPendingChanges { get; }


Property Value

Boolean

Name

Gets or sets the value of the BrowseNameOpcAttribute which defines the non-localizable human-readable name used when browsing the address space.

C#

OpcName Name { get; set; }


Property Value

OpcName



Remarks

The Name should never be used to display the name of the a node. Use the DisplayName instead for this purpose.

Unlike node identifiers the Name cannot be used to unambiguously identify the node. Different nodes may have the same browse name. The namespace is provided to make the browse name unique in some cases in the context of a node (e.g. properties of a node) although not unique in the context of the server. If different organizations define browse names for properties, the namespace of the Name provided by the organization makes the Name unique, although different organizations may use the same string having a slightly different meaning. Servers may often choose to use the same namespace for the node identifier and the browse name. However, if they want to provide a standard property, its browse name shall have the namespace of the standards body although the namespace of the node identifier reflects something else, for example the local server.

It is recommended that standard bodies defining standard type definitions use their namespace for the node identifier of the type definition node as well as for the browse name of the type definition node.

The String-part of the browse name is case sensitive. That is, clients shall consider them case sensitive. Server are allowed to handle browse names passed in service requests as case insensitive.

Use the value of this property to construct browse paths (see OpcNamePath).

Namespace

C#

OpcNamespace Namespace { get; }


Property Value

OpcNamespace

Parent

C#

IOpcNode Parent { get; }


Property Value

IOpcNode

PendingChanges

C#

OpcNodeChanges PendingChanges { get; }


Property Value

OpcNodeChanges

Tag

Gets or sets the object that contains additional user data about the node.

C#

object Tag { get; set; }


Property Value

Object

An Object that contains additional user data about the node. The default is null (Nothing in Visual Basic).

UserWriteAccess

Gets or sets the value of the optional UserWriteAccessOpcAttribute which exposes the possibilities of a client to write the attributes of the node taking user access rights into account.

C#

OpcAttributeWriteAccess UserWriteAccess { get; set; }


Property Value

OpcAttributeWriteAccess

A combination of the members defined by the OpcAttributeWriteAccess enumeration.



Remarks

The mask value of this attribute can only further restrict the WriteAccess attribute, when it is set to not writable in the general case that applies for every user.

WriteAccess

Gets or sets the value of the optional WriteAccessOpcAttribute which exposes the posibilities of a client to write the attributes of the node.

C#

OpcAttributeWriteAccess WriteAccess { get; set; }


Property Value

OpcAttributeWriteAccess

A combination of the members defined by the OpcAttributeWriteAccess enumeration.



Remarks

The mask value of this attribute does not take any user access rights into account, that is, altough an attribute is writable this may be restricted to a certain user / user group.

If a server does not have the ability to get the write mask information for a specific attribute from the underlying system, it should state that it is writable. If a write opertation is called on the attribute, the server should transfer this request and return the corresponding OpcStatusCode if such a request is rejected.

Only in case there a corresponding attribute is set in the mask of this attribute the according attribute is writable; otherwise it can not accessed for writing.

AddNotifier(OpcContext, IOpcNode)

C#

void AddNotifier(OpcContext context, IOpcNode node)


Parameters

context OpcContext


node IOpcNode




Exceptions

ArgumentNullException


ApplyChanges(OpcContext)

C#

void ApplyChanges(OpcContext context)


Parameters

context OpcContext




Exceptions

ArgumentNullException


ApplyChanges(OpcContext, Boolean)

C#

void ApplyChanges(OpcContext context, bool recursive)


Parameters

context OpcContext


recursive Boolean




Exceptions

ArgumentNullException


Child(OpcContext, OpcName)

Retrieves the child node its Name property matches exactly the name specified.

C#

IOpcNode Child(OpcContext context, OpcName name)


Parameters

context OpcContext

The OpcContext to use to lookup the requested child node.

name OpcName

The full qualified OpcName of the node to lookup.


Returns

IOpcNode

An instance implementing the IOpcNode interface its Name exactly matches the name specified, if such a node is a known child node of this node. Otherwise a null reference (Nothing in Visual Basic).



Exceptions

ArgumentNullException

The context or name is a null reference (Nothing in Visual Basic).

Children(OpcContext)

Retrieves a sequence of all nodes organized as children of this node.

C#

IEnumerable<IOpcNode> Children(OpcContext context)


Parameters

context OpcContext

The OpcContext to use to lookup the child nodes.


Returns

IEnumerable<IOpcNode>

A sequence of instances implementing the IOpcNode interface which representing the nodes organized as child nodes of this node.



Exceptions

ArgumentNullException

The context is a null reference (Nothing in Visual Basic).

IsChangePending(OpcNodeChanges)

C#

bool IsChangePending(OpcNodeChanges change)


Parameters

change OpcNodeChanges



Returns

Boolean

RemoveNotifier(OpcContext, IOpcNode)

C#

void RemoveNotifier(OpcContext context, IOpcNode node)


Parameters

context OpcContext


node IOpcNode




Exceptions

ArgumentNullException