Reference

OpcClient.ReadNodes Method

Type

OpcClient

Namespace

Opc.UaFx.Client

Assembly

Opc.UaFx.Advanced.dll

Package

Opc.UaFx.Advanced v2.59.0

Members

OpcClient Members

Also in

Opc.UaFx.Client

10 overloads

Overload	Description
ReadNodes(IEnumerable<OpcNodeId>)	Reads the Value attribute of the nodes specified by nodeIds.
ReadNodes(params OpcNodeId[])	Reads the Value attribute of the nodes specified by nodeIds.
ReadNodes(OpcAttribute, IEnumerable<OpcNodeId>)	Reads the attribute of the nodes specified by nodeIds.
ReadNodes(OpcAttribute, params OpcNodeId[])	Reads the attribute of the nodes specified by nodeIds.
ReadNodes(OpcRange, IEnumerable<OpcNodeId>)since v2.24	Reads the range from the Value attribute of the nodes specified by nodeIds.
ReadNodes(OpcRange, params OpcNodeId[])since v2.24	Reads the range from the Value attribute of the nodes specified by nodeIds.
ReadNodes(OpcAttribute, OpcRange, IEnumerable<OpcNodeId>)since v2.24	Reads the range from the attribute of the nodes specified by nodeIds.
ReadNodes(OpcAttribute, OpcRange, params OpcNodeId[])since v2.24	Reads the range from the attribute of the nodes specified by nodeIds.
ReadNodes(IEnumerable<OpcReadNode>)	Reads one or more values of one or more attributes of one or more nodes using the specified commands.
ReadNodes(params OpcReadNode[])	Reads one or more values of one or more attributes of one or more nodes using the specified commands.

Known results: BadNodeIdInvalid, BadNodeIdUnknown, BadAttributeInvalid, BadIndexRangeInvalid, BadIndexRangeNoData, BadDataEncodingInvalid, BadDataEncodingUnsupported, BadNotReadable, BadUserAccessDenied

Exceptions (all overloads)

Exception	Condition
ObjectDisposedException	The object has been disposed of.
OpcException	The service execution failed upon different circumstances; for more details see exception details. The following issues can lead to that exception: BadNothingToDo, BadTooManyOperations, BadMaxAgeInvalid and BadTimestampsToReturnInvalid.

ReadNodes(IEnumerable<OpcNodeId>)

Reads the Value attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(IEnumerable<OpcNodeId> nodeIds)

Public Function ReadNodes(
    nodeIds As IEnumerable(Of OpcNodeId)) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
nodeIds	IEnumerable<OpcNodeId>	A sequence of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(params OpcNodeId[])

Reads the Value attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(params OpcNodeId[] nodeIds)

Public Function ReadNodes(
    ParamArray nodeIds As OpcNodeId()) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
nodeIds	params OpcNodeId[]	An array of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(OpcAttribute, IEnumerable<OpcNodeId>)

Reads the attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(
    OpcAttribute attribute,
    IEnumerable<OpcNodeId> nodeIds)

Public Function ReadNodes(
    attribute As OpcAttribute,
    nodeIds As IEnumerable(Of OpcNodeId)) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
attribute	OpcAttribute	One of the members defined by the OpcAttribute enumeration that defines which node attribute is to be used by the service.
nodeIds	IEnumerable<OpcNodeId>	A sequence of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(OpcAttribute, params OpcNodeId[])

Reads the attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(
    OpcAttribute attribute,
    params OpcNodeId[] nodeIds)

Public Function ReadNodes(
    attribute As OpcAttribute,
    ParamArray nodeIds As OpcNodeId()) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
attribute	OpcAttribute	One of the members defined by the OpcAttribute enumeration that defines which node attribute is to be used by the service.
nodeIds	params OpcNodeId[]	An array of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(OpcRange, IEnumerable<OpcNodeId>)

since v2.24

Reads the range from the Value attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(
    OpcRange range,
    IEnumerable<OpcNodeId> nodeIds)

Public Function ReadNodes(
    range As OpcRange,
    nodeIds As IEnumerable(Of OpcNodeId)) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
range	OpcRange	The OpcRange to use to identify the single element or range of elements to read.
nodeIds	IEnumerable<OpcNodeId>	A sequence of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(OpcRange, params OpcNodeId[])

since v2.24

Reads the range from the Value attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(
    OpcRange range,
    params OpcNodeId[] nodeIds)

Public Function ReadNodes(
    range As OpcRange,
    ParamArray nodeIds As OpcNodeId()) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
range	OpcRange	The OpcRange to use to identify the single element or range of elements to read.
nodeIds	params OpcNodeId[]	An array of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(OpcAttribute, OpcRange, IEnumerable<OpcNodeId>)

since v2.24

Reads the range from the attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(
    OpcAttribute attribute,
    OpcRange range,
    IEnumerable<OpcNodeId> nodeIds)

Public Function ReadNodes(
    attribute As OpcAttribute,
    range As OpcRange,
    nodeIds As IEnumerable(Of OpcNodeId)) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
attribute	OpcAttribute	One of the members defined by the OpcAttribute enumeration that defines which node attribute is to be used by the service.
range	OpcRange	The OpcRange to use to identify the single element or range of elements to read.
nodeIds	IEnumerable<OpcNodeId>	A sequence of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(OpcAttribute, OpcRange, params OpcNodeId[])

since v2.24

Reads the range from the attribute of the nodes specified by nodeIds.

public IEnumerable<OpcValue> ReadNodes(
    OpcAttribute attribute,
    OpcRange range,
    params OpcNodeId[] nodeIds)

Public Function ReadNodes(
    attribute As OpcAttribute,
    range As OpcRange,
    ParamArray nodeIds As OpcNodeId()) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
attribute	OpcAttribute	One of the members defined by the OpcAttribute enumeration that defines which node attribute is to be used by the service.
range	OpcRange	The OpcRange to use to identify the single element or range of elements to read.
nodeIds	params OpcNodeId[]	An array of OpcNodeId instances of the nodes to read.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the nodeIds sequence. There is for each node identifier one entry which stores the value requested.

Exceptions

Exception	Condition
ArgumentNullException	The nodeIds sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the nodeIds specified.

ReadNodes(IEnumerable<OpcReadNode>)

Reads one or more values of one or more attributes of one or more nodes using the specified commands.

public IEnumerable<OpcValue> ReadNodes(IEnumerable<OpcReadNode> commands)

Public Function ReadNodes(
    commands As IEnumerable(Of OpcReadNode)) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
commands	IEnumerable<OpcReadNode>	A sequence of OpcReadNode instances to process.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the commands sequence. There is for each command one entry which stores the value requested by that command.

Exceptions

Exception	Condition
ArgumentNullException	The commands sequence or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the commands specified.

ReadNodes(params OpcReadNode[])

Reads one or more values of one or more attributes of one or more nodes using the specified commands.

public IEnumerable<OpcValue> ReadNodes(params OpcReadNode[] commands)

Public Function ReadNodes(
    ParamArray commands As OpcReadNode()) As IEnumerable(Of OpcValue)

Parameters

Name	Type	Description
commands	params OpcReadNode[]	An array of OpcReadNode instances to process.

Returns

IEnumerable<OpcValue>

A sequence of OpcValue instances its number and order of items matches the number and order of items in the commands sequence. There is for each command one entry which stores the value requested by that command.

Exceptions

Exception	Condition
ArgumentNullException	The commands array or one of its items is a null reference (Nothing in Visual Basic).
InvalidOperationException	The read service is currently not supported, especially using the commands specified.