QOpcUaHistoryReadResponse Class
该类用于请求历史数据并存储结果。更多内容...
| 头文件: | #include <QOpcUaHistoryReadResponse> |
| CMake: | find_package(Qt6 REQUIRED COMPONENTS OpcUa) target_link_libraries(mytarget PRIVATE Qt6::OpcUa) |
| qmake: | QT += opcua |
| 鉴于: | Qt 6.3 |
| 继承自: | QObject |
公共类型
| enum class | State { Unknown, Reading, Finished, MoreDataAvailable, Error } |
公共函数
| virtual | ~QOpcUaHistoryReadResponse() |
| QList<QOpcUaHistoryData> | data() const |
(since 6.7) QList<QOpcUaHistoryEvent> | events() const |
| bool | hasMoreData() const |
| bool | readMoreData() |
| bool | releaseContinuationPoints() |
| QOpcUa::UaStatusCode | serviceResult() const |
| QOpcUaHistoryReadResponse::State | state() const |
信号
| void | readHistoryDataFinished(const QList<QOpcUaHistoryData> &results, QOpcUa::UaStatusCode serviceResult) |
(since 6.7) void | readHistoryEventsFinished(const QList<QOpcUaHistoryEvent> &results, QOpcUa::UaStatusCode serviceResult) |
| void | stateChanged(QOpcUaHistoryReadResponse::State state) |
详细说明
对 OPC UA 服务器的历史数据请求可通过QOpcUaHistoryReadRawRequest 或QOpcUaHistoryReadEventRequest 指定。
该类的对象和请求的状态码将根据请求类型,分别返回在QOpcUaHistoryReadResponse::readHistoryDataFinished (const QList<QOpcUaHistoryData> &results, QOpcUa::UaStatusCode serviceResult)或QOpcUaHistoryReadResponse::readHistoryEventsFinished (const QList<QOpcUaHistoryEvent> &results, QOpcUa::UaStatusCode serviceResult) 信号中返回,具体取决于请求类型,其中包含请求的结果。
成员类型文档
enum class QOpcUaHistoryReadResponse::State
此枚举用于指定响应所处的状态。
| 常量 | 值 |
|---|---|
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
[virtual noexcept] QOpcUaHistoryReadResponse::~QOpcUaHistoryReadResponse()
的析构函数QOpcUaHistoryReadResponse
QList<QOpcUaHistoryData> QOpcUaHistoryReadResponse::data() const
返回一个包含所请求历史数据的列表。
[since 6.7] QList<QOpcUaHistoryEvent> QOpcUaHistoryReadResponse::events() const
返回一个QOpcUaHistoryEvent 列表,其中包含请求中每个待读取节点的事件列表。
该函数于 Qt 6.7 中引入。
bool QOpcUaHistoryReadResponse::hasMoreData() const
如果历史数据请求中还有更多可用值,则返回true 。
[signal] void QOpcUaHistoryReadResponse::readHistoryDataFinished(const QList<QOpcUaHistoryData> &results, QOpcUa::UaStatusCode serviceResult)
当历史数据请求完成时,会发出此信号。它会向results 添加条目,并将serviceResult 设置为相应值以指示结果的状态。
另请参阅 data() 和serviceResult()。
[signal, since 6.7] void QOpcUaHistoryReadResponse::readHistoryEventsFinished(const QList<QOpcUaHistoryEvent> &results, QOpcUa::UaStatusCode serviceResult)
当历史事件请求完成时,会发出此信号。新的历史数据及任何先前数据将通过results 返回,而serviceResult 则指示结果的状态。
该函数在 Qt 6.7 中引入。
另请参阅 events() 和serviceResult()。
bool QOpcUaHistoryReadResponse::readMoreData()
如果成功分发读取更多历史值的请求,则返回true 。
bool QOpcUaHistoryReadResponse::releaseContinuationPoints()
释放延续点,并将请求标记为已完成。如果待处理请求已成功完成,则返回true ;否则返回false。
QOpcUa::UaStatusCode QOpcUaHistoryReadResponse::serviceResult() const
返回历史数据请求的服务结果。
QOpcUaHistoryReadResponse::State QOpcUaHistoryReadResponse::state() const
返回历史数据请求的当前状态。
[signal] void QOpcUaHistoryReadResponse::stateChanged(QOpcUaHistoryReadResponse::State state)
当历史数据请求的条件发生变化时,会发出此信号。它会将state 设置为相应值,以指示变化的状态。
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