QXmlDefaultHandler 类提供所有 XML 处理程序类的默认实现。 更多...
头: | #include <QXmlDefaultHandler> |
CMake: |
find_package(Qt6 COMPONENTS Core5Compat REQUIRED)
target_link_libraries(mytarget PRIVATE Qt6::Core5Compat) |
qmake: | QT += core5compat |
继承: | QXmlContentHandler , QXmlErrorHandler , QXmlDTDHandler , QXmlEntityResolver , QXmlLexicalHandler ,和 QXmlDeclHandler |
注意: 此类的所有函数 可重入 .
QXmlDefaultHandler () | |
virtual | ~QXmlDefaultHandler () |
virtual bool | attributeDecl (const QString & eName , const QString & aName , const QString & type , const QString & valueDefault , const QString & value ) override |
virtual bool | characters (const QString & ch ) override |
virtual bool | comment (const QString & ch ) override |
virtual bool | endCDATA () override |
virtual bool | endDTD () override |
virtual bool | endDocument () override |
virtual bool | endElement (const QString & namespaceURI , const QString & localName , const QString & qName ) override |
virtual bool | endEntity (const QString & name ) override |
virtual bool | endPrefixMapping (const QString & prefix ) override |
virtual bool | error (const QXmlParseException & exception ) override |
virtual QString | errorString () const override |
virtual bool | externalEntityDecl (const QString & name , const QString & publicId , const QString & systemId ) override |
virtual bool | fatalError (const QXmlParseException & exception ) override |
virtual bool | ignorableWhitespace (const QString & ch ) override |
virtual bool | internalEntityDecl (const QString & name , const QString & value ) override |
virtual bool | notationDecl (const QString & name , const QString & publicId , const QString & systemId ) override |
virtual bool | processingInstruction (const QString & target , const QString & data ) override |
virtual bool | resolveEntity (const QString & publicId , const QString & systemId , QXmlInputSource *& ret ) override |
virtual void | setDocumentLocator (QXmlLocator * locator ) override |
virtual bool | skippedEntity (const QString & name ) override |
virtual bool | startCDATA () override |
virtual bool | startDTD (const QString & name , const QString & publicId , const QString & systemId ) override |
virtual bool | startDocument () override |
virtual bool | startElement (const QString & namespaceURI , const QString & localName , const QString & qName , const QXmlAttributes & atts ) override |
virtual bool | startEntity (const QString & name ) override |
virtual bool | startPrefixMapping (const QString & prefix , const QString & uri ) override |
virtual bool | unparsedEntityDecl (const QString & name , const QString & publicId , const QString & systemId , const QString & notationName ) override |
virtual bool | warning (const QXmlParseException & exception ) override |
This class gathers together the features of the specialized handler classes, making it a convenient starting point when implementing custom handlers for subclasses of QXmlReader , particularly QXmlSimpleReader . The virtual functions from each of the base classes are reimplemented in this class, providing sensible default behavior for many common cases. By subclassing this class, and overriding these functions, you can concentrate on implementing the parts of the handler relevant to your application.
The XML reader must be told which handler to use for different kinds of events during parsing. This means that, although QXmlDefaultHandler provides default implementations of functions inherited from all its base classes, we can still use specialized handlers for particular kinds of events.
For example, QXmlDefaultHandler subclasses both QXmlContentHandler and QXmlErrorHandler , so by subclassing it we can use the same handler for both of the following reader functions:
xmlReader.setContentHandler(handler); xmlReader.setErrorHandler(handler);
Since the reader will inform the handler of parsing errors, it is necessary to reimplement QXmlErrorHandler::fatalError () if, for example, we want to stop parsing when such an error occurs:
bool Handler::fatalError (const QXmlParseException & exception) { qWarning() << "Fatal error on line" << exception.lineNumber() << ", column" << exception.columnNumber() << ':' << exception.message(); return false; }
The above function returns
false
, which tells the reader to stop parsing. To continue to use the same reader, it is necessary to create a new handler instance, and set up the reader to use it in the manner described above.
It is useful to examine some of the functions inherited by QXmlDefaultHandler, and consider why they might be reimplemented in a custom handler. Custom handlers will typically reimplement QXmlContentHandler::startDocument () to prepare the handler for new content. Document elements and the text within them can be processed by reimplementing QXmlContentHandler::startElement (), QXmlContentHandler::endElement (),和 QXmlContentHandler::characters (). You may want to reimplement QXmlContentHandler::endDocument () to perform some finalization or validation on the content once the document has been read completely.
另请参阅 QXmlDTDHandler , QXmlDeclHandler , QXmlContentHandler , QXmlEntityResolver , QXmlErrorHandler ,和 QXmlLexicalHandler .
Constructs a handler for use with subclasses of QXmlReader .
[virtual]
QXmlDefaultHandler::
~QXmlDefaultHandler
()
Destroys the handler.
[override virtual]
bool
QXmlDefaultHandler::
attributeDecl
(const
QString
&
eName
, const
QString
&
aName
, const
QString
&
type
, const
QString
&
valueDefault
, const
QString
&
value
)
重实现: QXmlDeclHandler::attributeDecl (const QString &eName, const QString &aName, const QString &type, const QString &valueDefault, const QString &value).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
characters
(const
QString
&
ch
)
重实现: QXmlContentHandler::characters (const QString &ch).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
comment
(const
QString
&
ch
)
重实现: QXmlLexicalHandler::comment (const QString &ch).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
endCDATA
()
重实现: QXmlLexicalHandler::endCDATA ().
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
endDTD
()
重实现: QXmlLexicalHandler::endDTD ().
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
endDocument
()
重实现: QXmlContentHandler::endDocument ().
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
endElement
(const
QString
&
namespaceURI
, const
QString
&
localName
, const
QString
&
qName
)
重实现: QXmlContentHandler::endElement (const QString &namespaceURI, const QString &localName, const QString &qName).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
endEntity
(const
QString
&
name
)
重实现: QXmlLexicalHandler::endEntity (const QString &name).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
endPrefixMapping
(const
QString
&
prefix
)
重实现: QXmlContentHandler::endPrefixMapping (const QString &prefix).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
error
(const
QXmlParseException
&
exception
)
重实现: QXmlErrorHandler::error (const QXmlParseException &exception).
This reimplementation does nothing.
[override virtual]
QString
QXmlDefaultHandler::
errorString
() const
重实现: QXmlContentHandler::errorString () const.
Returns the default error string.
[override virtual]
bool
QXmlDefaultHandler::
externalEntityDecl
(const
QString
&
name
, const
QString
&
publicId
, const
QString
&
systemId
)
重实现: QXmlDeclHandler::externalEntityDecl (const QString &name, const QString &publicId, const QString &systemId).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
fatalError
(const
QXmlParseException
&
exception
)
重实现: QXmlErrorHandler::fatalError (const QXmlParseException &exception).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
ignorableWhitespace
(const
QString
&
ch
)
重实现: QXmlContentHandler::ignorableWhitespace (const QString &ch).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
internalEntityDecl
(const
QString
&
name
, const
QString
&
value
)
重实现: QXmlDeclHandler::internalEntityDecl (const QString &name, const QString &value).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
notationDecl
(const
QString
&
name
, const
QString
&
publicId
, const
QString
&
systemId
)
重实现: QXmlDTDHandler::notationDecl (const QString &name, const QString &publicId, const QString &systemId).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
processingInstruction
(const
QString
&
target
, const
QString
&
data
)
重实现: QXmlContentHandler::processingInstruction (const QString &target, const QString &data).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
resolveEntity
(const
QString
&
publicId
, const
QString
&
systemId
,
QXmlInputSource
*&
ret
)
重实现: QXmlEntityResolver::resolveEntity (const QString &publicId, const QString &systemId, QXmlInputSource *&ret).
设置
ret
to
nullptr
, so that the reader uses the system identifier provided in the XML document.
[override virtual]
void
QXmlDefaultHandler::
setDocumentLocator
(
QXmlLocator
*
locator
)
重实现: QXmlContentHandler::setDocumentLocator (QXmlLocator *locator).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
skippedEntity
(const
QString
&
name
)
重实现: QXmlContentHandler::skippedEntity (const QString &name).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
startCDATA
()
重实现: QXmlLexicalHandler::startCDATA ().
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
startDTD
(const
QString
&
name
, const
QString
&
publicId
, const
QString
&
systemId
)
重实现: QXmlLexicalHandler::startDTD (const QString &name, const QString &publicId, const QString &systemId).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
startDocument
()
重实现: QXmlContentHandler::startDocument ().
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
startElement
(const
QString
&
namespaceURI
, const
QString
&
localName
, const
QString
&
qName
, const
QXmlAttributes
&
atts
)
重实现: QXmlContentHandler::startElement (const QString &namespaceURI, const QString &localName, const QString &qName, const QXmlAttributes &atts).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
startEntity
(const
QString
&
name
)
重实现: QXmlLexicalHandler::startEntity (const QString &name).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
startPrefixMapping
(const
QString
&
prefix
, const
QString
&
uri
)
重实现: QXmlContentHandler::startPrefixMapping (const QString &prefix, const QString &uri).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
unparsedEntityDecl
(const
QString
&
name
, const
QString
&
publicId
, const
QString
&
systemId
, const
QString
&
notationName
)
重实现: QXmlDTDHandler::unparsedEntityDecl (const QString &name, const QString &publicId, const QString &systemId, const QString ¬ationName).
This reimplementation does nothing.
[override virtual]
bool
QXmlDefaultHandler::
warning
(const
QXmlParseException
&
exception
)
重实现: QXmlErrorHandler::warning (const QXmlParseException &exception).
This reimplementation does nothing.