Reference

OpcNodeHistory<T> Members

Type

OpcNodeHistory<T>

Namespace

Opc.UaFx.Server

Assembly

Opc.UaFx.Advanced.dll

Package

Opc.UaFx.Advanced v2.59.0

Constructors

OpcNodeHistory

6 overloads

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

OpcNodeHistory()

Initializes a new instance of the OpcNodeHistory<T> class whose Capacity is -1 (unlimited).

public OpcNodeHistory()

Public Sub New()

OpcNodeHistory(int)

Initializes a new instance of the OpcNodeHistory<T> class using the capacity specified.

public OpcNodeHistory(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.

OpcNodeHistory(IEnumerable<T>)

Initializes a new instance of the OpcNodeHistory<T> class using the values specified. The number of values the history keeps is not limited.

public OpcNodeHistory(IEnumerable<T> values)

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

Parameters

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

Exceptions

Exception	Condition
ArgumentException	Two of the values have the same timestamp.
ArgumentNullException	The values or one of its items is a null reference (Nothing in Visual Basic).

OpcNodeHistory(int, IEnumerable<T>)

Initializes a new instance of the OpcNodeHistory<T> class using the capacity and values specified.

public OpcNodeHistory(int capacity, IEnumerable<T> values)

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

Parameters

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

Exceptions

Exception	Condition
ArgumentException	Two of the added values have the same timestamp.
ArgumentNullException	The values or one of the added items is a null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	The capacity is 0 or less than -1.

Remarks

If the capacity is not -1, only the last capacity items of the sequence are added, regardless of their timestamps.

OpcNodeHistory(params T[])

Initializes a new instance of the OpcNodeHistory<T> class using the values specified. The number of values the history keeps is not limited.

public OpcNodeHistory(params T[] values)

Public Sub New(ParamArray values As T())

Parameters

Name	Type	Description
values	params T[]	The values to add to the history.

Exceptions

Exception	Condition
ArgumentException	Two of the values have the same timestamp.
ArgumentNullException	The values or one of its items is a null reference (Nothing in Visual Basic).

OpcNodeHistory(int, params T[])

Initializes a new instance of the OpcNodeHistory<T> class using the capacity and values specified.

public OpcNodeHistory(int capacity, params T[] values)

Public Sub New(capacity As Integer, ParamArray values As T())

Parameters

Name	Type	Description
capacity	Int32	The maximum number of values the history keeps: -1 (unlimited) or a positive number.
values	params T[]	The values to add to the history.

Exceptions

Exception	Condition
ArgumentException	Two of the added values have the same timestamp.
ArgumentNullException	The values or one of the added items is a null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	The capacity is 0 or less than -1.

Remarks

If the capacity is not -1, only the last capacity items of the array are added, regardless of their timestamps.

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 value with the earliest timestamp is removed first, also if the value added is earlier, and 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 in the history.

EnableRaisingEvents

Gets or sets a value indicating whether the history raises the events Added, Removed and Replaced.

public bool EnableRaisingEvents { get; set; }

Public Property EnableRaisingEvents As Boolean

Property value

Boolean

The value true if the history raises the events; 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 latest timestamp 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 earliest timestamp or a null reference (Nothing in Visual Basic) if the history is empty.

Methods

Add

Adds the value specified to the history and raises the Added event.

public void Add(T value)

Public Sub Add(value As T)

Parameters

Name	Type	Description
value	T	The value to add.

Exceptions

Exception	Condition
ArgumentException	The history already contains a value with the timestamp of the value.
ArgumentNullException	The value is a null reference (Nothing in Visual Basic).

Remarks

If the history has reached its Capacity, the value with the earliest timestamp is removed first.

AddRange

2 overloads

Overload	Description
AddRange(IEnumerable<T>)	Adds the values specified to the history and raises the Added event.
AddRange(params T[])	Adds the values specified to the history and raises the Added event.

Exceptions (all overloads)

Exception	Condition
ArgumentException	The history already contains a value with the timestamp of one of the values.
ArgumentNullException	The values or one of its items is a null reference (Nothing in Visual Basic).

AddRange(IEnumerable<T>)

Adds the values specified to the history and raises the Added event.

public void AddRange(IEnumerable<T> values)

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

Parameters

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

Remarks

The values are added in the order of the sequence. If a value cannot be added, the method stops and throws the exception; the values added before remain in the history. For a value which already exists, the Added event provides the values added before; for an item which is a null reference, the event is not raised.

AddRange(params T[])

Adds the values specified to the history and raises the Added event.

public void AddRange(params T[] values)

Public Sub AddRange(ParamArray values As T())

Parameters

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

Remarks

The values are added in the order of the array. If a value cannot be added, the method stops and throws the exception; the values added before remain in the history. For a value which already exists, the Added event provides the values added before; for an item which is a null reference, the event is not raised.

Clear

Removes all values from the history and raises the Removed event.

public void Clear()

Public Sub Clear()

Contains

2 overloads

Overload	Description
Contains(DateTime)	Determines whether the history contains a value at the timestamp specified.
Contains(T)	Determines whether the history contains the value specified.

Contains(DateTime)

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

public bool Contains(DateTime timestamp)

Public Function Contains(timestamp As Date) As Boolean

Parameters

Name	Type	Description
timestamp	DateTime	The timestamp to look for.

Returns

Boolean

The value true if the history contains a value at the timestamp; otherwise the value false.

Contains(T)

Determines whether the history contains the value specified.

public bool Contains(T value)

Public Function Contains(value As T) As Boolean

Parameters

Name	Type	Description
value	T	The value to look for.

Returns

Boolean

The value true if the value of the history at the timestamp of the value is equal to the value; otherwise the value false.

Exceptions

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

Enumerate

3 overloads

Overload	Description
Enumerate()	Enumerates the values of the history in ascending order of their timestamps.
Enumerate(DateTime?)
Enumerate(DateTime?, DateTime?)

Enumerate()

Enumerates the values of the history in ascending order of their timestamps.

public IEnumerable<T> Enumerate()

Public Function Enumerate() As IEnumerable(Of T)

Returns

IEnumerable<T>

A sequence of the values of the history.

Remarks

The history stays locked while the sequence is enumerated, so that other threads which access the history wait until the enumeration has completed or the enumerator has been disposed.

Enumerate(DateTime?)

public IEnumerable<T> Enumerate(DateTime? startTime)

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

Parameters

Name	Type	Description
startTime	Nullable<DateTime>

Returns

IEnumerable<T>

Enumerate(DateTime?, DateTime?)

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

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

Parameters

Name	Type	Description
startTime	Nullable<DateTime>
endTime	Nullable<DateTime>

Returns

IEnumerable<T>

GetEnumerator

Returns an enumerator which iterates through the values of the history in ascending order of their timestamps.

public IEnumerator<T> GetEnumerator()

Public Function GetEnumerator() As IEnumerator(Of T)

Returns

IEnumerator<T>

An enumerator for the values of the history.

Implements

GetEnumerator()

Remarks

The history stays locked while the enumerator is used, so that other threads which access the history wait until the enumeration has completed or the enumerator has been disposed.

OnAdded

protected · virtual

Raises the Added event using the specified event data.

protected virtual void OnAdded(OpcNodeHistoryEventArgs<T> e)

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

Parameters

Name	Type	Description
e	OpcNodeHistoryEventArgs<T>	The OpcNodeHistoryEventArgs<T> with the values added.

OnRemoved

protected · virtual

Raises the Removed event using the specified event data.

protected virtual void OnRemoved(OpcNodeHistoryEventArgs<T> e)

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

Parameters

Name	Type	Description
e	OpcNodeHistoryEventArgs<T>	The OpcNodeHistoryEventArgs<T> with the values removed.

OnReplaced

protected · virtual

Raises the Replaced event using the specified event data.

protected virtual void OnReplaced(OpcNodeHistoryEventArgs<T> e)

Protected Overridable Sub OnReplaced(e As OpcNodeHistoryEventArgs(Of T))

Parameters

Name	Type	Description
e	OpcNodeHistoryEventArgs<T>	The OpcNodeHistoryEventArgs<T> with the values replaced.

Remove

Removes the value specified from the history and raises the Removed event.

public bool Remove(T value)

Public Function Remove(value As T) As Boolean

Parameters

Name	Type	Description
value	T	The value to remove.

Returns

Boolean

The value true if the history contained the value (see Contains) and the value has been removed; otherwise the value false.

Exceptions

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

RemoveAt

4 overloads

Overload	Description
RemoveAt(int)	Removes the value at the index specified in the ascending order of the timestamps and raises the Removed event.
RemoveAt(DateTime)	Removes the value at the timestamp specified and raises the Removed event.
RemoveAt(IEnumerable<DateTime>)	Removes the values at the timestamps specified and raises the Removed event.
RemoveAt(params DateTime[])	Removes the values at the timestamps specified and raises the Removed event.

RemoveAt(int)

Removes the value at the index specified in the ascending order of the timestamps and raises the Removed event.

public void RemoveAt(int index)

Public Sub RemoveAt(index As Integer)

Parameters

Name	Type	Description
index	Int32	The zero-based index of the value to remove.

Exceptions

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

RemoveAt(DateTime)

Removes the value at the timestamp specified and raises the Removed event.

public void RemoveAt(DateTime timestamp)

Public Sub RemoveAt(timestamp As Date)

Parameters

Name	Type	Description
timestamp	DateTime	The timestamp of the value to remove.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	The history contains no value at the timestamp.

RemoveAt(IEnumerable<DateTime>)

Removes the values at the timestamps specified and raises the Removed event.

public void RemoveAt(IEnumerable<DateTime> timestamps)

Public Sub RemoveAt(timestamps As IEnumerable(Of Date))

Parameters

Name	Type	Description
timestamps	IEnumerable<DateTime>	A sequence of the timestamps of the values to remove.

Exceptions

Exception	Condition
ArgumentNullException	The timestamps is a null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	The history contains no value at one of the timestamps.

Remarks

The values are removed in the order of the sequence. If the history contains no value at a timestamp, the method stops and throws the exception; the values removed before stay removed.

RemoveAt(params DateTime[])

Removes the values at the timestamps specified and raises the Removed event.

public void RemoveAt(params DateTime[] timestamps)

Public Sub RemoveAt(ParamArray timestamps As Date())

Parameters

Name	Type	Description
timestamps	params DateTime[]	The timestamps of the values to remove.

Exceptions

Exception	Condition
ArgumentNullException	The timestamps is a null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	The history contains no value at one of the timestamps.

Remarks

The values are removed in the order of the array. If the history contains no value at a timestamp, the method stops and throws the exception; the values removed before stay removed.

RemoveRange

2 overloads

Overload	Description
RemoveRange(DateTime?)
RemoveRange(DateTime?, DateTime?)

RemoveRange(DateTime?)

public void RemoveRange(DateTime? startTime)

Public Sub RemoveRange(startTime As Date?)

Parameters

Name	Type	Description
startTime	Nullable<DateTime>

Exceptions

Exception	Condition
ArgumentOutOfRangeException

RemoveRange(DateTime?, DateTime?)

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

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

Parameters

Name	Type	Description
startTime	Nullable<DateTime>
endTime	Nullable<DateTime>

Replace

Replaces the value at the timestamp of the value specified with the value and raises the Replaced event.

public void Replace(T value)

Public Sub Replace(value As T)

Parameters

Name	Type	Description
value	T	The new value.

Exceptions

Exception	Condition
ArgumentException	The history contains no value at the timestamp of the value.
ArgumentNullException	The value is a null reference (Nothing in Visual Basic).

Events

Added

Occurs after values have been added to the history.

public event EventHandler<OpcNodeHistoryEventArgs<T>> Added

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

Event type

EventHandler<OpcNodeHistoryEventArgs<T>>

Remarks

A method which adds several values raises the event once for all values added, also if no value has been added. The event is not raised while EnableRaisingEvents is false.

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<T>> Removed

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

Event type

EventHandler<OpcNodeHistoryEventArgs<T>>

Remarks

A method which removes several values raises the event once for all values removed, also if no value has been removed. The event is not raised while EnableRaisingEvents is false.

Replaced

Occurs after a value of the history has been replaced.

public event EventHandler<OpcNodeHistoryEventArgs<T>> Replaced

Public Event Replaced As EventHandler(Of OpcNodeHistoryEventArgs(Of T))

Event type

EventHandler<OpcNodeHistoryEventArgs<T>>

Remarks

The Values of the event data provide the values which have been replaced, not the new values. The event is not raised while EnableRaisingEvents is false.

Indexers

Item

2 overloads

Overload	Description
this[int]	Gets or sets the value at the index specified in the ascending order of the timestamps.
this[DateTime]	Gets or sets the value at the timestamp specified.

this[int]

Gets or sets the value at the index specified in the ascending order of the timestamps.

public T this[int index] { get; set; }

Public Default Property this[](index As Integer) As T

Parameters

Name	Type	Description
index	Int32	The zero-based index of the value.

Property value

T

The value at the index specified.

Exceptions

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

Remarks

The setter replaces the value at the timestamp of the value at the index without comparing the timestamp of the new value and raises the Replaced event. To replace a value by its own timestamp use Replace.

this[DateTime]

Gets or sets the value at the timestamp specified.

public T this[DateTime timestamp] { get; set; }

Public Default Property this[](timestamp As Date) As T

Parameters

Name	Type	Description
timestamp	DateTime	The timestamp of the value.

Property value

T

The value at the timestamp specified.

Exceptions

Exception	Condition
KeyNotFoundException	The history contains no value at the timestamp specified.

Remarks

The setter replaces the value at the timestamp without comparing the timestamp of the new value and raises the Replaced event. To replace a value by its own timestamp use Replace.