Reference

OpcHistoryValue Members

Type

OpcHistoryValue

Namespace

Opc.UaFx

Assembly

Opc.UaFx.Advanced.dll

Package

Opc.UaFx.Advanced v2.59.0

Also in

Opc.UaFx.Client

Inherits members from OpcValue.

Constructors

OpcHistoryValue

3 overloads

Overload	Description
OpcHistoryValue(object, DateTime)	Initializes a new instance of the OpcHistoryValue class using the value and timestamp specified.
OpcHistoryValue(object, DateTime, OpcStatus)	Initializes a new instance of the OpcHistoryValue class using the value, timestamp and status specified.
OpcHistoryValue(object, DateTime, OpcStatusCode)	Initializes a new instance of the OpcHistoryValue class using the value, timestamp and statusCode specified.

OpcHistoryValue(object, DateTime)

Initializes a new instance of the OpcHistoryValue class using the value and timestamp specified.

public OpcHistoryValue(object value, DateTime timestamp)

Public Sub New(value As Object, timestamp As Date)

Parameters

Name	Type	Description
value	Object	The value.
timestamp	DateTime	The time of the value, which is used as the source and the server timestamp.

OpcHistoryValue(object, DateTime, OpcStatus)

Initializes a new instance of the OpcHistoryValue class using the value, timestamp and status specified.

public OpcHistoryValue(object value, DateTime timestamp, OpcStatus status)

Public Sub New(value As Object, timestamp As Date, status As OpcStatus)

Parameters

Name	Type	Description
value	Object	The value.
timestamp	DateTime	The time of the value, which is used as the source and the server timestamp.
status	OpcStatus	The status of the value.

OpcHistoryValue(object, DateTime, OpcStatusCode)

Initializes a new instance of the OpcHistoryValue class using the value, timestamp and statusCode specified.

[CLSCompliant(false)]
public OpcHistoryValue(
    object value,
    DateTime timestamp,
    OpcStatusCode statusCode)

<CLSCompliant(False)>
Public Sub New(value As Object, timestamp As Date, statusCode As OpcStatusCode)

Parameters

Name	Type	Description
value	Object	The value.
timestamp	DateTime	The time of the value, which is used as the source timestamp.
statusCode	OpcStatusCode	The status code of the value.

Remarks

Unlike the other constructors, this constructor sets the source timestamp only; the server timestamp remains unset.

Properties

Timestamp

virtual

Gets the time of the value, by which the history is ordered.

public virtual DateTime Timestamp { get; }

Public Overridable ReadOnly Property Timestamp As Date

Property value

DateTime

The ServerTimestamp or, if it is not set, the SourceTimestamp; MinValue if neither is set.

Methods

CompareTo

Compares the current OpcHistoryValue with another OpcHistoryValue.

public int CompareTo(OpcHistoryValue other)

Public Function CompareTo(other As OpcHistoryValue) As Integer

Parameters

Name	Type	Description
other	OpcHistoryValue	The OpcHistoryValue to compare with this OpcHistoryValue.

Returns

Int32

A 32-bit signed integer that indicates the relative order of the objects being compared (CompareTo(T)).

Create

static · 2 overloads

Overload	Description
Create(OpcValue)static	Creates an OpcHistoryValue from the value specified.
Create<T>(OpcVariableValue<T>)static	Creates an OpcHistoryValue from the value of a variable node.

Exceptions (all overloads)

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

Create(OpcValue)

static

Creates an OpcHistoryValue from the value specified.

public static OpcHistoryValue Create(OpcValue value)

Public Shared Function Create(value As OpcValue) As OpcHistoryValue

Parameters

Name	Type	Description
value	OpcValue	The value providing the data of the history value.

Returns

OpcHistoryValue

An OpcHistoryValue holding the data of the value.

Remarks

The history value uses a copy of the data of the value, so that a change of one value does not change the other.

Create<T>(OpcVariableValue<T>)

static

Creates an OpcHistoryValue from the value of a variable node.

public static OpcHistoryValue Create<T>(OpcVariableValue<T> value)

Public Shared Function Create(Of T)(
    value As OpcVariableValue(Of T)) As OpcHistoryValue

Type parameters

Name	Description
T	The type of the value.

Parameters

Name	Type	Description
value	OpcVariableValue<T>	The value of the variable node.

Returns

OpcHistoryValue

An OpcHistoryValue using the value, the status and the timestamp of the value, or the current time (UTC) if it has no timestamp.

CreateModified

6 overloads

Overload	Description
CreateModified(OpcHistoryModificationType)	Creates an OpcModifiedHistoryValue from this value using a modification of the modificationType specified at the current time (UTC).
CreateModified(OpcHistoryModificationType, string)	Creates an OpcModifiedHistoryValue from this value using a modification of the modificationType by the userName specified at the current time (UTC).
CreateModified(OpcHistoryModificationType, string, DateTime)	Creates an OpcModifiedHistoryValue from this value using a modification of the modificationType by the userName at the timestamp specified.
CreateModified(OpcHistoryModificationType, string, DateTime, object)	Creates an OpcModifiedHistoryValue from this value using the value and a modification of the modificationType by the userName at the timestamp specified.
CreateModified(OpcHistoryModificationInfo)	Creates an OpcModifiedHistoryValue from this value using the modificationInfo specified.
CreateModified(OpcHistoryModificationInfo, object)	Creates an OpcModifiedHistoryValue from this value using the modificationInfo and the value specified.

CreateModified(OpcHistoryModificationType)

Creates an OpcModifiedHistoryValue from this value using a modification of the modificationType specified at the current time (UTC).

public OpcModifiedHistoryValue CreateModified(
    OpcHistoryModificationType modificationType)

Public Function CreateModified(
    modificationType As OpcHistoryModificationType) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
modificationType	OpcHistoryModificationType	The kind of the modification.

Returns

OpcModifiedHistoryValue

An OpcModifiedHistoryValue holding the data of this value.

Remarks

The modified value shares the data of this value, so that a change of the data of one value also changes the data of the other.

CreateModified(OpcHistoryModificationType, string)

Creates an OpcModifiedHistoryValue from this value using a modification of the modificationType by the userName specified at the current time (UTC).

public OpcModifiedHistoryValue CreateModified(
    OpcHistoryModificationType modificationType,
    string userName)

Public Function CreateModified(
    modificationType As OpcHistoryModificationType,
    userName As String) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
modificationType	OpcHistoryModificationType	The kind of the modification.
userName	String	The name of the user who made the modification.

Returns

OpcModifiedHistoryValue

An OpcModifiedHistoryValue holding the data of this value.

Remarks

The modified value shares the data of this value, so that a change of the data of one value also changes the data of the other.

CreateModified(OpcHistoryModificationType, string, DateTime)

Creates an OpcModifiedHistoryValue from this value using a modification of the modificationType by the userName at the timestamp specified.

public OpcModifiedHistoryValue CreateModified(
    OpcHistoryModificationType modificationType,
    string userName,
    DateTime timestamp)

Public Function CreateModified(
    modificationType As OpcHistoryModificationType,
    userName As String,
    timestamp As Date) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
modificationType	OpcHistoryModificationType	The kind of the modification.
userName	String	The name of the user who made the modification.
timestamp	DateTime	The time of the modification.

Returns

OpcModifiedHistoryValue

An OpcModifiedHistoryValue holding the data of this value.

Remarks

The modified value shares the data of this value, so that a change of the data of one value also changes the data of the other.

CreateModified(OpcHistoryModificationType, string, DateTime, object)

Creates an OpcModifiedHistoryValue from this value using the value and a modification of the modificationType by the userName at the timestamp specified.

public OpcModifiedHistoryValue CreateModified(
    OpcHistoryModificationType modificationType,
    string userName,
    DateTime timestamp,
    object value)

Public Function CreateModified(
    modificationType As OpcHistoryModificationType,
    userName As String,
    timestamp As Date,
    value As Object) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
modificationType	OpcHistoryModificationType	The kind of the modification.
userName	String	The name of the user who made the modification.
timestamp	DateTime	The time of the modification.
value	Object	The value of the modified value.

Returns

OpcModifiedHistoryValue

An OpcModifiedHistoryValue holding a copy of the data of this value with the value specified.

Remarks

The status and the timestamps of the modified value are those of this value. This value remains unchanged.

CreateModified(OpcHistoryModificationInfo)

Creates an OpcModifiedHistoryValue from this value using the modificationInfo specified.

public OpcModifiedHistoryValue CreateModified(
    OpcHistoryModificationInfo modificationInfo)

Public Function CreateModified(
    modificationInfo As OpcHistoryModificationInfo) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
modificationInfo	OpcHistoryModificationInfo	The information about the modification.

Returns

OpcModifiedHistoryValue

An OpcModifiedHistoryValue holding the data of this value.

Exceptions

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

Remarks

The modified value shares the data of this value, so that a change of the data of one value also changes the data of the other.

CreateModified(OpcHistoryModificationInfo, object)

Creates an OpcModifiedHistoryValue from this value using the modificationInfo and the value specified.

public OpcModifiedHistoryValue CreateModified(
    OpcHistoryModificationInfo modificationInfo,
    object value)

Public Function CreateModified(
    modificationInfo As OpcHistoryModificationInfo,
    value As Object) As OpcModifiedHistoryValue

Parameters

Name	Type	Description
modificationInfo	OpcHistoryModificationInfo	The information about the modification.
value	Object	The value of the modified value.

Returns

OpcModifiedHistoryValue

An OpcModifiedHistoryValue holding a copy of the data of this value with the value specified.

Exceptions

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

Remarks

The status and the timestamps of the modified value are those of this value. This value remains unchanged.

Equals

2 overloads

Overload	Description
Equals(object)override	Determines whether the specified other is equal to this OpcHistoryValue.
Equals(OpcHistoryValue)	Determines whether the specified other is equal to this OpcHistoryValue.

Equals(object)

override

Determines whether the specified other is equal to this OpcHistoryValue.

public override bool Equals(object other)

Public Overrides Function Equals(other As Object) As Boolean

Parameters

Name	Type	Description
other	Object	The OpcHistoryValue to compare to the current OpcHistoryValue.

Returns

Boolean

The value true if the specified OpcHistoryValue is equal to the current OpcHistoryValue; otherwise the value false.

Overrides

Equals

Equals(OpcHistoryValue)

Determines whether the specified other is equal to this OpcHistoryValue.

public bool Equals(OpcHistoryValue other)

Public Function Equals(other As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
other	OpcHistoryValue	The OpcHistoryValue to compare to the current OpcHistoryValue.

Returns

Boolean

The value true if the specified OpcHistoryValue is equal to the current OpcHistoryValue; otherwise the value false.

GetHashCode

override

Retrieves a hash code for this OpcHistoryValue.

public override int GetHashCode()

Public Overrides Function GetHashCode() As Integer

Returns

Int32

An int that contains the hash code for the OpcHistoryValue.

Overrides

GetHashCode

ToString

override · 2 overloads

Overload	Description
ToString()override	Returns a string that represents the history value.
ToString(string, IFormatProvider)override	Returns a string that represents the history value using the format and formatProvider specified.

ToString()

override

Returns a string that represents the history value.

public override string ToString()

Public Overrides Function ToString() As String

Returns

String

A string containing the Timestamp and the string representation of the value.

Overrides

ToString

ToString(string, IFormatProvider)

override

Returns a string that represents the history value using the format and formatProvider specified.

public override string ToString(string format, IFormatProvider formatProvider)

Public Overrides Function ToString(
    format As String,
    formatProvider As IFormatProvider) As String

Parameters

Name	Type	Description
format	String	The format to use for the value.
formatProvider	IFormatProvider	The provider to use to format the value.

Returns

String

A string containing the Timestamp and the formatted value.

Overrides

ToString

Operators

Equality

static

Returns a value indicating whether two instance of OpcHistoryValue are equal.

public static bool operator ==(OpcHistoryValue left, OpcHistoryValue right)

Public Shared Operator =(
    left As OpcHistoryValue,
    right As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
left	OpcHistoryValue	The first OpcHistoryValue to compare.
right	OpcHistoryValue	The second OpcHistoryValue to compare.

Returns

Boolean

The value true if left and right are equal; otherwise the value false.

GreaterThan

static

Determines whether the first specified OpcHistoryValue object is greater than the second specified OpcHistoryValue object.

public static bool operator >(OpcHistoryValue left, OpcHistoryValue right)

Public Shared Operator >(
    left As OpcHistoryValue,
    right As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
left	OpcHistoryValue	The first OpcHistoryValue object.
right	OpcHistoryValue	The second OpcHistoryValue object.

Returns

Boolean

The value true if left is greater than right; otherwise, false.

GreaterThanOrEqual

static

Determines whether the first specified OpcHistoryValue object is greater than or equal to the second specified OpcHistoryValue object.

public static bool operator >=(OpcHistoryValue left, OpcHistoryValue right)

Public Shared Operator >=(
    left As OpcHistoryValue,
    right As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
left	OpcHistoryValue	The first OpcHistoryValue object.
right	OpcHistoryValue	The second OpcHistoryValue object.

Returns

Boolean

The value true if left is greater than or equal to right; otherwise, false.

Inequality

static

Returns a value indicating whether two instances of OpcHistoryValue are not equal.

public static bool operator !=(OpcHistoryValue left, OpcHistoryValue right)

Public Shared Operator <>(
    left As OpcHistoryValue,
    right As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
left	OpcHistoryValue	The first OpcHistoryValue to compare.
right	OpcHistoryValue	The second OpcHistoryValue to compare.

Returns

Boolean

The value true if left and right are not equal; otherwise the value false.

LessThan

static

Determines whether the first specified OpcHistoryValue object is less than the second specified OpcHistoryValue object.

public static bool operator <(OpcHistoryValue left, OpcHistoryValue right)

Public Shared Operator <(
    left As OpcHistoryValue,
    right As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
left	OpcHistoryValue	The first OpcHistoryValue object.
right	OpcHistoryValue	The second OpcHistoryValue object.

Returns

Boolean

The value true if left is less than right; otherwise the value false.

Exceptions

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

LessThanOrEqual

static

Determines whether the first specified OpcHistoryValue object is less than or equal to the second OpcHistoryValue object.

public static bool operator <=(OpcHistoryValue left, OpcHistoryValue right)

Public Shared Operator <=(
    left As OpcHistoryValue,
    right As OpcHistoryValue) As Boolean

Parameters

Name	Type	Description
left	OpcHistoryValue	The first OpcHistoryValue object.
right	OpcHistoryValue	The second OpcHistoryValue object.

Returns

Boolean

The value true if left is less than or equal to right; otherwise the value false.

Exceptions

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