The QMqttTopicFilter class represents a MQTT topic filter. More...
| Header: | #include <QMqttTopicFilter> |
| CMake: | find_package(Qt6 REQUIRED COMPONENTS Mqtt) target_link_libraries(mytarget PRIVATE Qt6::Mqtt) |
| qmake: | QT += mqtt |
Note: All functions in this class are reentrant.
| enum | MatchOption { NoMatchOption, WildcardsDontMatchDollarTopicMatchOption } |
| flags | MatchOptions |
| QMqttTopicFilter(const QMqttTopicFilter &filter) | |
| QMqttTopicFilter(const QLatin1String &filter) | |
| QMqttTopicFilter(const QString &filter = QString()) | |
| QMqttTopicFilter & | operator=(const QMqttTopicFilter &filter) |
| ~QMqttTopicFilter() | |
| QString | filter() const |
| bool | isValid() const |
| bool | match(const QMqttTopicName &name, QMqttTopicFilter::MatchOptions matchOptions = NoMatchOption) const |
| void | setFilter(const QString &filter) |
| QString | sharedSubscriptionName() const |
| void | swap(QMqttTopicFilter &other) |
| bool | operator!=(const QMqttTopicFilter &lhs, const QMqttTopicFilter &rhs) |
| bool | operator<(const QMqttTopicFilter &lhs, const QMqttTopicFilter &rhs) |
| QDataStream & | operator<<(QDataStream &out, const QMqttTopicFilter &filter) |
| bool | operator==(const QMqttTopicFilter &lhs, const QMqttTopicFilter &rhs) |
| QDataStream & | operator>>(QDataStream &in, QMqttTopicFilter &filter) |
QMqttTopicFilter is a thin wrapper around a QString providing an expressive data type for MQTT topic filters. Beside the benefits of having a strong type preventing unintended misuse, QMqttTopicFilter provides convenient functions related to topic filters like isValid() or match().
For example, the following code would fail to compile and prevent a possible unintended and meaningless matching of two filters, especially if the variable names were less expressive:
QMqttTopicFilter globalFilter{"foo/#"}; QMqttTopicFilter specificFilter{"foo/bar"}; if (globalFilter.match(specificFilter)) { //... }
The usability, however, is not affected since the following snippet compiles and runs as expected:
QMqttTopicFilter globalFilter{"foo/#"}; if (globalFilter.match("foo/bar")) { //... }
See also QMqttTopicName.
This enum value holds the matching options for the topic filter.
| Constant | Value | Description |
|---|---|---|
QMqttTopicFilter::NoMatchOption |
0x0000 |
No match options are set. |
QMqttTopicFilter::WildcardsDontMatchDollarTopicMatchOption |
0x0001 |
A wildcard at the filter's beginning does not match a topic name that starts with the dollar sign ($). |
The MatchOptions type is a typedef for QFlags<MatchOption>. It stores an OR combination of MatchOption values.
Creates a new MQTT topic filter as a copy of filter.
Creates a new MQTT topic filter with the specified filter.
Creates a new MQTT topic filter with the specified filter.
Assigns the MQTT topic filter filter to this object, and returns a reference to the copy.
Destroys the QMqttTopicFilter object.
Returns the topic filter.
See also setFilter().
Returns true if the topic filter is valid according to the MQTT standard section 4.7, or false otherwise.
Returns true if the topic filter matches the topic name name honoring the given matchOptions, or false otherwise.
Sets the topic filter to filter.
See also filter().
[since 5.12] QString QMqttTopicFilter::sharedSubscriptionName() constReturns the name of a share if the topic filter has been specified as a shared subscription. The format of shared subscriptions is defined as $share/sharename/topicfilter.
This function was introduced in Qt 5.12.
Swaps the MQTT topic filter other with this MQTT topic filter. This operation is very fast and never fails.
Returns true if the topic filters lhs and rhs are different, otherwise returns false.
Returns true if the topic filter lhs is lexically less than the topic filter rhs; otherwise returns false.
Writes the topic filter filter to the stream out and returns a reference to the stream.
See also Format of the QDataStream operators.
Returns true if the topic filters lhs and rhs are equal, otherwise returns false.
Reads a topic filter into filter from the stream in and returns a reference to the stream.
See also Format of the QDataStream operators.
