Namespace: Opc.UaFx
Assemblies: Opc.UaFx.Advanced.dll, Opc.UaFx.Advanced.dll
The OpcEventNode type exposes the following members.
Initializes a new instance of the OpcEventNode class accessible by the name
specified as a child node of the parent
node given.
C#
public OpcEventNode(IOpcNode parent, OpcName name)
Parameters
parent
IOpcNode
The IOpcNode used as the parent node or a null reference (Nothing in Visual Basic) in the case there is no parent node available.
name
OpcName
The OpcName through that the new event node can be accessed.
Initializes a new instance of the OpcEventNode class accessible by the name
and id
specified as a child node of the parent
node given.
C#
public OpcEventNode(IOpcNode parent, OpcName name, OpcNodeId id)
Parameters
parent
IOpcNode
The IOpcNode used as the parent node or a null reference (Nothing in Visual Basic) in the case there is no parent node available.
name
OpcName
The OpcName through that the new event node can be accessed.
id
OpcNodeId
The OpcNodeId through that the new event node can be identified and accessed.
Initializes a new instance of the OpcEventNode class accessible by the name
specified.
C#
public OpcEventNode(OpcName name)
Parameters
name
OpcName
The OpcName through that the new event node can be accessed.
Initializes a new instance of the OpcEventNode class accessible by the name
and id
specified.
C#
public OpcEventNode(OpcName name, OpcNodeId id)
Parameters
name
OpcName
The OpcName through that the new event node can be accessed.
id
OpcNodeId
The OpcNodeId through that the new event node can be identified and accessed.
Gets the default identifier which identifies the node that defines the underlying node type from that this OpcInstanceNode has been created.
C#
protected override OpcNodeId DefaultTypeDefinitionId { get; }
Property Value
The OpcNodeId of the type node from that this OpcInstanceNode has been created from. These type node defines the typical structure of an instance node of its type definition. If there exists no specific type definition node a null reference (Nothing in Visual Basic).
Gets or sets a value generated by the server to uniquely identify a particular event notification.
C#
public byte[] EventId { get; set; }
Property Value
Byte[]
The server is responsible to ensure that each event has its unique event identifier. It may do this, for example, by putting GUIDs into the ByteString. Clients can use the event identifier to assist in minimizing or eliminating gaps and overlaps that may occur during a redundancy failover. The event identifier shall always be returned as value and the server is not allowed to return a status code for the event identifier indicating an error.
Gets the OpcPropertyNode´1 of the EventId property.
C#
public OpcPropertyNode<byte[]> EventIdNode { get; }
Property Value
An instance of the OpcPropertyNode´1 class.
Gets or sets the node identifier which describes the specific type of event.
C#
public OpcNodeId EventTypeId { get; set; }
Property Value
The event type shall always be returned as value and the server is not allowed to return a status code for the event type indicating an error.
Gets the OpcNodeIdPropertyNode of the EventTypeId property.
C#
public OpcNodeIdPropertyNode EventTypeIdNode { get; }
Property Value
An instance of the OpcNodeIdPropertyNode class.
Gets or sets a value which defines a human-readable and localizable text description of the event.
C#
public OpcText Message { get; set; }
Property Value
The server may return any appropriate text to describe the event. A null reference (Nothing in Visual Basic) if it is not a valid value; if the server does not have a description, it shall return the string part of the Name of the node associated with the event.
Gets the OpcTextPropertyNode of the Message property.
C#
public OpcTextPropertyNode MessageNode { get; }
Property Value
An instance of the OpcTextPropertyNode class.
Gets or sets the time the OPC UA server received the event from the underlying device of another server.
C#
public DateTime ReceiveTime { get; set; }
Property Value
The ReceiveTime is analogous to the ServerTimestamp, i.e. in the case where the OPC UA server gets an event from another OPC UA server, each server applies its own ReceiveTime. That implies that a client may get the same event, having the same EventId, from different servers having different values of the ReceiveTime. The ReceiveTime shall always be returned as value and the server is not allowed to return a status code for the ReceiveTime indicating an error.
Gets the OpcPropertyNode´1 of the ReceiveTime property.
C#
public OpcPropertyNode<DateTime> ReceiveTimeNode { get; }
Property Value
An instance of the OpcPropertyNode´1 class.
Gets or sets an indication of the urgency of the event.
C#
public OpcEventSeverity Severity { get; set; }
Property Value
This value is commonly called “priority”. Values will range from 1 to 1 000, with 1 being the lowest severity and 1 000 being the highest. Typically, a severity of 1 would indicate an event which is informational in nature, while a value of 1 000 would indicate an event of catastrophic nature, which could potentially result in severe financial loss or loss of life.
Remarks
It is expected that very few server implementations will support 1 000 distinct severity levels. Therefore, server developers are responsible for distributing their severity levels across the 1 to 1 000 range in such a manner that clients can assume a linear distribution.
In many cases a strict linear mapping of underlying source severities to the OPC severity range is not appropriate. The server developer will instead intelligently map the underlying source severities to the 1 to 1 000 OPC severity range in some other fashion. In particular, it is recommended that server developers map events of high urgency into the OPC severity range of 667 to 1 000, events of medium urgency into the OPC severity range of 334 to 666 and events of low urgency into OPC severities of 1 to 333.
Some servers might not support any events which are catastrophic in nature, so they may choose to map all of their severities into a subset of the 1 to 1 000 range (for example, 1 to 666). Other servers might not support any events which are merely informational, so they may choose to map all of their severities into a different subset of the 1 to 1 000 range (for example, 334 to 1 000).
The purpose of this approach is to allow clients to use severity values from multiple servers from different vendors in a consistent manner.
Gets the OpcPropertyNode´1 of the Severity property.
C#
[CLSCompliant(false)] public OpcPropertyNode<ushort> SeverityNode { get; }
Property Value
An instance of the OpcPropertyNode´1 class.
Gets or sets a description of the source of the event.
C#
public string SourceName { get; set; }
Property Value
A value which can be a string-part of the DisplayName of the event source using the default locale of the server, if the event is specific to a node, or some server-specific notation.
Gets the OpcPropertyNode´1 of the SourceName property.
C#
public OpcPropertyNode<string> SourceNameNode { get; }
Property Value
An instance of the OpcPropertyNode´1 class.
Gets or sets the node identifier which identifies the node that the event originated from.
C#
public OpcNodeId SourceNodeId { get; set; }
Property Value
If the event is not specific to a node the value is a null reference (Nothing in Visual Basic); otherwise the OpcNodeId of the node that the event originated from. Some subtypes of this OpcEventNode may define additional rules for the SourceNodeId.
Gets the OpcNodeIdPropertyNode of the SourceNodeId property.
C#
public OpcNodeIdPropertyNode SourceNodeIdNode { get; }
Property Value
An instance of the OpcNodeIdPropertyNode class.
Gets or sets the time the event occurred.
C#
public DateTime Time { get; set; }
Property Value
This value is set as close to the event generator as possible. It often comes from the underlying system or device. Once set, intermediate OPC UA servers shall not alter the value.
Gets the OpcPropertyNode´1 of the Time property.
C#
public OpcPropertyNode<DateTime> TimeNode { get; }
Property Value
An instance of the OpcPropertyNode´1 class.
Creates a new instance of the OpcEvent class which represents a snapshot of this OpcEventNode.
C#
public OpcEvent CreateEvent(OpcContext context)
Parameters
context
OpcContext
The OpcContext to use.
Returns
A new immutable instance of the OpcEvent class representing a snapshot of the event node data at the time this method has been called.
Creates a new instance of the OpcEvent class representing the specified snapshot
of this OpcEventNode.
C#
protected virtual OpcEvent CreateEventCore(OpcContext context, OpcEventNodeSnapshot snapshot)
Parameters
context
OpcContext
The OpcContext used to create the snapshot
.
snapshot
OpcEventNodeSnapshot
The OpcEventNodeSnapshot taken from the current state of this OpcEventNode from that the new OpcEvent is to be created.
Returns
A new instance of the OpcEvent representing an immutable snapshot
of this OpcEventNode.
Remarks
In case there this method is not overridden the method will determine the type of OpcEvent to use using the OpcEventTypeAttribute of the OpcEventNode and will use this one to create a new OpcEvent using the snapshot
specified.
Initializes the default values used by the OpcEventNode.
C#
protected override void InitializeDefaults()
Remarks
This method is used to ensure the availability of appropriate node specific default values. For more information like when this method is to be overwritten see InitializeDefaults.
Produces an event using the data represented by this OpcEventNode.
C#
public void ReportEvent(OpcContext context)
Parameters
context
OpcContext
The OpcContext to use.
Exceptions
The context
is a null reference (Nothing in Visual Basic).
Produces an event using the data represented by this OpcEventNode using the source
as initiator of the event reported.
C#
public void ReportEventFrom(OpcContext context, IOpcNode source)
Parameters
context
OpcContext
The OpcContext to use.
source
IOpcNode
The IOpcNode instance its Id is used for the SourceNodeId property and its SymbolicName is used for the SourceName property to define the origin of the event produced.
Exceptions
The context
or source
is a null reference (Nothing in Visual Basic).