QOpcUaProvider Class

QOpcUaProvider creates an instance of QOpcUaClient . 更多...

头：	#include <QOpcUaProvider>
qmake:	QT += opcua
继承：	QObject

所有成员列表，包括继承成员

公共函数

	QOpcUaProvider (QObject * parent = nullptr)
QOpcUaClient *	createClient (const QString & backend , const QVariantMap & backendProperties = QVariantMap())

静态公共成员

QStringList

availableBackends ()

详细描述

QOpcUaProvider allows the user to create an instance of QOpcUaClient by loading a QOpcUaPlugin using the Qt plugin system.

For the available plugins and their capabilities please refer to the introduction .

范例

This code creates a client using the first available backend:

QOpcUaProvider provider;
QStringList available = provider.availableBackends();
if (!available.isEmpty()) {
    QOpcUaClient *client = provider.createClient(available[0]);
    if (client)
        qDebug() << "Client successfully created";
}

成员函数文档编制

QOpcUaProvider:: QOpcUaProvider ( QObject * parent = nullptr)

Creates a new OPC UA provider with a given parent .

`[static]` QStringList QOpcUaProvider:: availableBackends ()

返回 QStringList of available plugins.

QOpcUaClient QOpcUaProvider:: createClient (const QString & backend* , const QVariantMap & backendProperties = QVariantMap())

返回指针指向 QOpcUaClient object by loading the selected backend as a plugin and creating a client object. If the plugin loading fails, nullptr 被返回取而代之。

The user is responsible for deleting the returned QOpcUaClient object when it is no longer needed.

The optional argument backendProperties can be used to pass custom backend specific settings as key value pairs. Those settings are specific to the backend being instantiated.

Available settings are

Setting string	Backend	描述
disableEncryptedPasswordCheck	Unified Automation	By default, the backend refuses to connect to endpoints without encryption to avoid sending passwords in clear text. This parameter allows to disable this feature.
enableVerboseDebugOutput	Unified Automation	Tells the backend to print additional output to the terminal. The backend specific logging level is set to `OPCUA_TRACE_OUTPUT_LEVEL_ALL` .
minimumClientIterateIntervalMs	open62541	Defines the client iterate interval for the backend. This value can be used to make a tradeoff between reaction time for subscriptions and CPU load. The default value is 50ms.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .