Reference

OpcModifiedNodeHistory Members

Type

OpcModifiedNodeHistory

Namespace

Opc.UaFx.Server

Assembly

Opc.UaFx.Advanced.dll

Package

Opc.UaFx.Advanced v2.59.0

Constructors

OpcModifiedNodeHistory

4 overloads

Overload	Description
OpcModifiedNodeHistory()	Initializes a new instance of the OpcModifiedNodeHistory class whose Capacity is -1 (unlimited).
OpcModifiedNodeHistory(int)	Initializes a new instance of the OpcModifiedNodeHistory class using the capacity specified.
OpcModifiedNodeHistory(IEnumerable<OpcModifiedHistoryValue>)	Initializes a new instance of the OpcModifiedNodeHistory class using the values specified.
OpcModifiedNodeHistory(int, IEnumerable<OpcModifiedHistoryValue>)	Initializes a new instance of the OpcModifiedNodeHistory class using the capacity and values specified.

OpcModifiedNodeHistory()

Initializes a new instance of the OpcModifiedNodeHistory class whose Capacity is -1 (unlimited).

public OpcModifiedNodeHistory()

Public Sub New()

OpcModifiedNodeHistory(int)

Initializes a new instance of the OpcModifiedNodeHistory class using the capacity specified.

public OpcModifiedNodeHistory(int capacity)

Public Sub New(capacity As Integer)

Parameters

Name	Type	Description
capacity	Int32	The maximum number of values the history keeps: -1 (unlimited) or a positive number.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	The capacity is 0 or less than -1.

OpcModifiedNodeHistory(IEnumerable<OpcModifiedHistoryValue>)

Initializes a new instance of the OpcModifiedNodeHistory class using the values specified.

public OpcModifiedNodeHistory(IEnumerable<OpcModifiedHistoryValue> values)

Public Sub New(values As IEnumerable(Of OpcModifiedHistoryValue))

Parameters

Name	Type	Description
values	IEnumerable<OpcModifiedHistoryValue>	A sequence of the values to add to the history.

Exceptions

Exception	Condition
ArgumentNullException	The values or one of its items is a null reference (Nothing in Visual Basic).

OpcModifiedNodeHistory(int, IEnumerable<OpcModifiedHistoryValue>)

Initializes a new instance of the OpcModifiedNodeHistory class using the capacity and values specified.

public OpcModifiedNodeHistory(
    int capacity,
    IEnumerable<OpcModifiedHistoryValue> values)

Public Sub New(
    capacity As Integer,
    values As IEnumerable(Of OpcModifiedHistoryValue))

Parameters

Name	Type	Description
capacity	Int32	The maximum number of values the history keeps: -1 (unlimited) or a positive number.
values	IEnumerable<OpcModifiedHistoryValue>	A sequence of the values to add to the history.

Exceptions

Exception	Condition
ArgumentNullException	The values or one of its items is a null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	The capacity is 0 or less than -1.

Remarks

The values are added like using AddRange, so that a history which reaches its Capacity removes values as described there.

Properties

Capacity

Gets the maximum number of values the history keeps.

public int Capacity { get; }

Public ReadOnly Property Capacity As Integer

Property value

Int32

The maximum number of values: -1 (unlimited) or a positive number.

Remarks

When a value is added to a history which has reached its capacity, the oldest modification is removed first, regardless of the timestamps of the values: the value with the earliest ModificationTime and, for the same modification time, the value added first. Then the Removed event is raised.

Count

Gets the number of values in the history.

public int Count { get; }

Public ReadOnly Property Count As Integer

Property value

Int32

The number of values, counting each modification of a value.

EnableRaisingEvents

Gets or sets a value indicating whether the history raises its events.

public bool EnableRaisingEvents { get; set; }

Public Property EnableRaisingEvents As Boolean

Property value

Boolean

The value true to raise the events Added and Removed; otherwise the value false. The default value is true.

EndTime

Gets the latest timestamp of the values in the history.

public DateTime? EndTime { get; }

Public ReadOnly Property EndTime As Date?

Property value

Nullable<DateTime>

The timestamp of the last value or a null reference (Nothing in Visual Basic) if the history is empty.

StartTime

Gets the earliest timestamp of the values in the history.

public DateTime? StartTime { get; }

Public ReadOnly Property StartTime As Date?

Property value

Nullable<DateTime>

The timestamp of the first value or a null reference (Nothing in Visual Basic) if the history is empty.

Methods

Add

Adds the value specified to the history.

public void Add(OpcModifiedHistoryValue value)

Public Sub Add(value As OpcModifiedHistoryValue)

Parameters

Name	Type	Description
value	OpcModifiedHistoryValue	The value to add.

Exceptions

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

Remarks

A value whose timestamp is already in the history is added as a further modification of the value at that time.

AddRange

2 overloads

Overload	Description
AddRange(IEnumerable<OpcModifiedHistoryValue>)	Adds the values specified to the history.
AddRange(params OpcModifiedHistoryValue[])	Adds the values specified to the history.

Exceptions (all overloads)

Exception	Condition
ArgumentNullException	The values or one of its items is a null reference (Nothing in Visual Basic).

AddRange(IEnumerable<OpcModifiedHistoryValue>)

Adds the values specified to the history.

public void AddRange(IEnumerable<OpcModifiedHistoryValue> values)

Public Sub AddRange(values As IEnumerable(Of OpcModifiedHistoryValue))

Parameters

Name	Type	Description
values	IEnumerable<OpcModifiedHistoryValue>	A sequence of the values to add.

Remarks

No value is added if one of the items is a null reference.

AddRange(params OpcModifiedHistoryValue[])

Adds the values specified to the history.

public void AddRange(params OpcModifiedHistoryValue[] values)

Public Sub AddRange(ParamArray values As OpcModifiedHistoryValue())

Parameters

Name	Type	Description
values	params OpcModifiedHistoryValue[]	The values to add.

Remarks

No value is added if one of the items is a null reference.

Clear

Removes all values from the history.

public void Clear()

Public Sub Clear()

Contains

Determines whether the history contains a value with the timestamp specified.

public bool Contains(DateTime timestamp)

Public Function Contains(timestamp As Date) As Boolean

Parameters

Name	Type	Description
timestamp	DateTime	The timestamp of the value.

Returns

Boolean

The value true if the history contains at least one value with the timestamp; otherwise the value false.

Enumerate

3 overloads

Overload	Description
Enumerate()	Gets the values of the history in their sort order.
Enumerate(DateTime?)	Gets the values whose timestamp is not earlier than the startTime specified.
Enumerate(DateTime?, DateTime?)	Gets the values whose timestamp is within the time range specified, including its bounds.

Enumerate()

Gets the values of the history in their sort order.

public IEnumerable<OpcModifiedHistoryValue> Enumerate()

Public Function Enumerate() As IEnumerable(Of OpcModifiedHistoryValue)

Returns

IEnumerable<OpcModifiedHistoryValue>

A sequence of all values.

Remarks

The sequence is a snapshot of the history.

Enumerate(DateTime?)

Gets the values whose timestamp is not earlier than the startTime specified.

public IEnumerable<OpcModifiedHistoryValue> Enumerate(DateTime? startTime)

Public Function Enumerate(
    startTime As Date?) As IEnumerable(Of OpcModifiedHistoryValue)

Parameters

Name	Type	Description
startTime	Nullable<DateTime>	The earliest timestamp of the values to get. A null reference (Nothing in Visual Basic), MinValue or MaxValue does not limit the time range.

Returns

IEnumerable<OpcModifiedHistoryValue>

A sequence of the values within the time range.

Remarks

The sequence is a snapshot of the history.

Enumerate(DateTime?, DateTime?)

Gets the values whose timestamp is within the time range specified, including its bounds.

public IEnumerable<OpcModifiedHistoryValue> Enumerate(
    DateTime? startTime,
    DateTime? endTime)

Public Function Enumerate(
    startTime As Date?,
    endTime As Date?) As IEnumerable(Of OpcModifiedHistoryValue)

Parameters

Name	Type	Description
startTime	Nullable<DateTime>	One bound of the time range. A null reference (Nothing in Visual Basic), MinValue or MaxValue does not limit the time range.
endTime	Nullable<DateTime>	The other bound of the time range, with the same values for an unlimited bound as the startTime.

Returns

IEnumerable<OpcModifiedHistoryValue>

A sequence of the values within the time range.

Remarks

If the startTime is later than the endTime, the bounds are swapped. The sequence is a snapshot of the history.

GetEnumerator

Returns an enumerator which iterates through the values of the history.

public IEnumerator<OpcModifiedHistoryValue> GetEnumerator()

Public Function GetEnumerator() As IEnumerator(Of OpcModifiedHistoryValue)

Returns

IEnumerator<OpcModifiedHistoryValue>

An enumerator of a snapshot of the history.

Implements

GetEnumerator()

GetValues

Gets the values with the timestamp specified.

public IEnumerable<OpcModifiedHistoryValue> GetValues(DateTime timestamp)

Public Function GetValues(
    timestamp As Date) As IEnumerable(Of OpcModifiedHistoryValue)

Parameters

Name	Type	Description
timestamp	DateTime	The timestamp of the values.

Returns

IEnumerable<OpcModifiedHistoryValue>

A sequence of the modifications of the value at the timestamp, from the most recent to the oldest modification; an empty sequence if there is no value with the timestamp.

OnAdded

protected · virtual

Raises the Added event.

protected virtual void OnAdded(
    OpcNodeHistoryEventArgs<OpcModifiedHistoryValue> e)

Protected Overridable Sub OnAdded(
    e As OpcNodeHistoryEventArgs(Of OpcModifiedHistoryValue))

Parameters

Name	Type	Description
e	OpcNodeHistoryEventArgs<OpcModifiedHistoryValue>	The event data.

OnRemoved

protected · virtual

Raises the Removed event.

protected virtual void OnRemoved(
    OpcNodeHistoryEventArgs<OpcModifiedHistoryValue> e)

Protected Overridable Sub OnRemoved(
    e As OpcNodeHistoryEventArgs(Of OpcModifiedHistoryValue))

Parameters

Name	Type	Description
e	OpcNodeHistoryEventArgs<OpcModifiedHistoryValue>	The event data.

RemoveAt

Removes the value at the index specified.

public void RemoveAt(int index)

Public Sub RemoveAt(index As Integer)

Parameters

Name	Type	Description
index	Int32	The zero-based index of the value in the sort order of the history.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	The index is less than zero or not less than Count.

RemoveRange

2 overloads

Overload	Description
RemoveRange(DateTime?)	Removes the values whose timestamp is not earlier than the startTime specified.
RemoveRange(DateTime?, DateTime?)	Removes the values whose timestamp is within the time range specified, including its bounds.

RemoveRange(DateTime?)

Removes the values whose timestamp is not earlier than the startTime specified.

public void RemoveRange(DateTime? startTime)

Public Sub RemoveRange(startTime As Date?)

Parameters

Name	Type	Description
startTime	Nullable<DateTime>	The earliest timestamp of the values to remove. A null reference (Nothing in Visual Basic), MinValue or MaxValue does not limit the time range.

Remarks

The Removed event is raised once for all values removed, also if no value has been removed.

RemoveRange(DateTime?, DateTime?)

Removes the values whose timestamp is within the time range specified, including its bounds.

public void RemoveRange(DateTime? startTime, DateTime? endTime)

Public Sub RemoveRange(startTime As Date?, endTime As Date?)

Parameters

Name	Type	Description
startTime	Nullable<DateTime>	One bound of the time range. A null reference (Nothing in Visual Basic), MinValue or MaxValue does not limit the time range.
endTime	Nullable<DateTime>	The other bound of the time range, with the same values for an unlimited bound as the startTime.

Remarks

If the startTime is later than the endTime, the bounds are swapped. The Removed event is raised once for all values removed, also if no value has been removed.

Events

Added

Occurs after values have been added to the history.

public event EventHandler<OpcNodeHistoryEventArgs<OpcModifiedHistoryValue>> Added

Public Event Added As EventHandler(Of OpcNodeHistoryEventArgs(Of OpcModifiedHistoryValue))

Event type

EventHandler<OpcNodeHistoryEventArgs<OpcModifiedHistoryValue>>

Removed

Occurs after values have been removed from the history, also if a value has been removed because the history reached its Capacity.

public event EventHandler<OpcNodeHistoryEventArgs<OpcModifiedHistoryValue>> Removed

Public Event Removed As EventHandler(Of OpcNodeHistoryEventArgs(Of OpcModifiedHistoryValue))

Event type

EventHandler<OpcNodeHistoryEventArgs<OpcModifiedHistoryValue>>

Indexers

Item

Gets the value at the index specified.

public OpcModifiedHistoryValue this[int index] { get; }

Public ReadOnly Default Property this[](
    index As Integer) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
index	Int32	The zero-based index of the value in the sort order of the history.

Property value

OpcModifiedHistoryValue

The value at the index.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	The index is less than zero or not less than Count.