Reference

OpcReadNodesRequest Members

Type

OpcReadNodesRequest

Namespace

Opc.UaFx.Services

Assembly

Opc.UaFx.Advanced.dll

Package

Opc.UaFx.Advanced v2.59.0

Also in

Opc.UaFx.Client

Inherits members from OpcServiceRequest<OpcReadNode, OpcReadNodeCollection>, OpcServiceRequest.

Constructors

OpcReadNodesRequest

4 overloads

Overload	Description
OpcReadNodesRequest(IEnumerable<OpcReadNode>)	Initializes a new instance of the OpcReadNodesRequest class using the specified commands and a new header.
OpcReadNodesRequest(params OpcReadNode[])	Initializes a new instance of the OpcReadNodesRequest class using the specified commands and a new header.
OpcReadNodesRequest(IOpcServiceRequestHeader, IEnumerable<OpcReadNode>)since v2.7	Initializes a new instance of the OpcReadNodesRequest class using the specified header and commands.
OpcReadNodesRequest(IOpcServiceRequestHeader, params OpcReadNode[])since v2.7	Initializes a new instance of the OpcReadNodesRequest class using the specified header and commands.

OpcReadNodesRequest(IEnumerable<OpcReadNode>)

Initializes a new instance of the OpcReadNodesRequest class using the specified commands and a new header.

public OpcReadNodesRequest(IEnumerable<OpcReadNode> commands)

Public Sub New(commands As IEnumerable(Of OpcReadNode))

Parameters

Name	Type	Description
commands	IEnumerable<OpcReadNode>	The commands which specify the attributes to read.

Exceptions

Exception	Condition
ArgumentNullException	The commands is a null reference (Nothing in Visual Basic).

OpcReadNodesRequest(params OpcReadNode[])

Initializes a new instance of the OpcReadNodesRequest class using the specified commands and a new header.

public OpcReadNodesRequest(params OpcReadNode[] commands)

Public Sub New(ParamArray commands As OpcReadNode())

Parameters

Name	Type	Description
commands	params OpcReadNode[]	The commands which specify the attributes to read.

Exceptions

Exception	Condition
ArgumentNullException	The commands is a null reference (Nothing in Visual Basic).

OpcReadNodesRequest(IOpcServiceRequestHeader, IEnumerable<OpcReadNode>)

since v2.7

Initializes a new instance of the OpcReadNodesRequest class using the specified header and commands.

public OpcReadNodesRequest(
    IOpcServiceRequestHeader header,
    IEnumerable<OpcReadNode> commands)

Public Sub New(
    header As IOpcServiceRequestHeader,
    commands As IEnumerable(Of OpcReadNode))

Parameters

Name	Type	Description
header	IOpcServiceRequestHeader	The header of the request.
commands	IEnumerable<OpcReadNode>	The commands which specify the attributes to read.

Exceptions

Exception	Condition
ArgumentNullException	The header or the commands is a null reference (Nothing in Visual Basic).

OpcReadNodesRequest(IOpcServiceRequestHeader, params OpcReadNode[])

since v2.7

Initializes a new instance of the OpcReadNodesRequest class using the specified header and commands.

public OpcReadNodesRequest(
    IOpcServiceRequestHeader header,
    params OpcReadNode[] commands)

Public Sub New(
    header As IOpcServiceRequestHeader,
    ParamArray commands As OpcReadNode())

Parameters

Name	Type	Description
header	IOpcServiceRequestHeader	The header of the request.
commands	params OpcReadNode[]	The commands which specify the attributes to read.

Exceptions

Exception	Condition
ArgumentNullException	The header or the commands is a null reference (Nothing in Visual Basic).

Properties

MaxAge

Gets or sets the maximum age in milliseconds of the values to read.

public double MaxAge { get; set; }

Public Property MaxAge As Double

Property value

Double

The maximum age of a value a server may provide from its cache: 0 for a value read from the data source; the default value is 0.

TimestampsToReturn

Gets or sets which timestamps of the values are to be returned.

public OpcTimestampsToReturn TimestampsToReturn { get; set; }

Public Property TimestampsToReturn As OpcTimestampsToReturn

Property value

OpcTimestampsToReturn

One of the members defined by the OpcTimestampsToReturn enumeration; the default value is Both.

Methods

Validate

protected · override · since v2.50

Validates the request before a server processes it.

protected override void Validate()

Protected Overrides Sub Validate()

Overrides

Validate

Remarks

A server rejects the request with BadNothingToDo if it contains no commands; then none of the commands is executed.