QOpcUaHistoryReadResponse Class

This class is used for requesting historical data and storing the results. 更多...

头: #include <QOpcUaHistoryReadResponse>
CMake: find_package(Qt6 REQUIRED COMPONENTS OpcUa)
target_link_libraries(mytarget PRIVATE Qt6::OpcUa)
qmake: QT += opcua
Since: Qt 6.3
继承: QObject

公共类型

enum class State { Unknown, Reading, Finished, MoreDataAvailable, Error }

公共函数

virtual ~QOpcUaHistoryReadResponse ()
QList<QOpcUaHistoryData> data () const
bool hasMoreData () const
bool readMoreData ()
bool releaseContinuationPoints ()
QOpcUa::UaStatusCode serviceResult () const
QOpcUaHistoryReadResponse::State state () const

信号

void readHistoryDataFinished (const QList<QOpcUaHistoryData> & 结果 , QOpcUa::UaStatusCode serviceResult )
void stateChanged (QOpcUaHistoryReadResponse::State state )

详细描述

A historical data request to an OPC UA server can be specified by a QOpcUaHistoryReadRawRequest .

Objects of this class and the statuscode of the request are returned in the QOpcUaHistoryReadResponse::readHistoryDataFinished (const QList<QOpcUaHistoryData> &results, QOpcUa::UaStatusCode serviceResult) signal and contain the result of a request.

成员类型文档编制

enum class QOpcUaHistoryReadResponse:: State

This enum specifies the state the response is in.

常量
QOpcUaHistoryReadResponse::State::Unknown 0
QOpcUaHistoryReadResponse::State::Reading 1
QOpcUaHistoryReadResponse::State::Finished 2
QOpcUaHistoryReadResponse::State::MoreDataAvailable 3
QOpcUaHistoryReadResponse::State::Error 4

成员函数文档编制

[虚拟] QOpcUaHistoryReadResponse:: ~QOpcUaHistoryReadResponse ()

The destructor for QOpcUaHistoryReadResponse

QList < QOpcUaHistoryData > QOpcUaHistoryReadResponse:: data () const

Returns a list which contains the requested historic data.

bool QOpcUaHistoryReadResponse:: hasMoreData () const

返回 true if there are more values available from the historic data request.

[signal] void QOpcUaHistoryReadResponse:: readHistoryDataFinished (const QList < QOpcUaHistoryData > & 结果 , QOpcUa::UaStatusCode serviceResult )

This signal is emitted when a historical data request is finished. It adds to results 并设置 serviceResult to indicate the state of the result.

另请参阅 data () 和 serviceResult ().

bool QOpcUaHistoryReadResponse:: readMoreData ()

返回 true if a read request for more historic values is successfully dispatched.

bool QOpcUaHistoryReadResponse:: releaseContinuationPoints ()

Releases the continuation points and sets the request as finished. Returns true if the pending request has been successfully finished; otherwise returns false.

QOpcUa::UaStatusCode QOpcUaHistoryReadResponse:: serviceResult () const

Returns the serviceresult of the historic data request.

QOpcUaHistoryReadResponse::State QOpcUaHistoryReadResponse:: state () const

Returns the current state of historic data request.

[signal] void QOpcUaHistoryReadResponse:: stateChanged ( QOpcUaHistoryReadResponse::State state )

This signal is emitted when the of a historical data request is changed. It sets state to indicate the state of the change.