QT中使用QXmlStreamReader解析XML文件

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XML文件由于其扩展性与兼容性的优点，被广泛用作软件和系统的配置文件。这里简要介绍一下QT下如何来解析XML文件。

 

源代码：

xml_reader.h

#ifndef XML_READER_H#define XML_READER_H#include <QtCore>//#include <QtGui>class xml_reader : public QXmlStreamReader{ //Q_OBJECTpublic: xml_reader(); bool read(QIODevice *device);private: void read_data(); void read_startweek(); void read_eventnumber(); void read_period(); void read_id(); void read_starttime(); void read_endtime(); void read_exception(); void read_subexception(); void read_description(); void read_duration(); void read_event(); void read_offsettime(); void read_eventdesc(); void read_eventname(); void read_prompt(); void read_lasthandle(); void read_unknow();};#endif // XML_READER_H 

xml_reader.cpp

#include "xml_reader.h"xml_reader::xml_reader(){}bool xml_reader::read(QIODevice *device){ setDevice(device); while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "data") { read_data(); } } } return !error();}void xml_reader::read_data(){ qDebug()<<"Start to read data..."; while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "period") { read_period(); } if(name() == "startweek") { read_startweek(); } if(name() == "eventnumber") { read_eventnumber(); } } if(isEndElement()) { if(name() == "data") { qDebug()<<"Now at the end of data element..."; break; } } }}void xml_reader::read_startweek(){ qDebug()<<"startweek is: "<<readElementText();}void xml_reader::read_eventnumber(){ qDebug()<<"eventNumber is: "<<readElementText();}void xml_reader::read_period(){ qDebug()<<"Start to read period..."; while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "id") { read_id(); } if(name() == "starttime") { read_starttime(); } if(name() == "endtime") { read_endtime(); } if(name() == "exception") { read_exception(); } if(name() == "duration") { read_duration(); } if(name() == "event") { read_event(); } } if(isEndElement()) { if(name() == "period") { qDebug()<<"Now at the end of period..."; break; } } }}void xml_reader::read_id(){ qDebug()<<"id is: " << readElementText();}void xml_reader::read_starttime(){ qDebug()<<"starttime is: " << readElementText();}void xml_reader::read_endtime(){ qDebug()<<"endtime is: " << readElementText();}void xml_reader::read_exception(){ qDebug()<<"Start to read exception..."; while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "subexception") { read_subexception(); } } if(isEndElement()) { if(name() == "exception") { qDebug()<<"Now at the end of exception..."; break; } } }}void xml_reader::read_subexception(){ qDebug()<<"Start to read subexception..."; while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "id") { read_id(); } if(name() == "starttime") { read_starttime(); } if(name() == "endtime") { read_endtime(); } if(name() == "description") { read_description(); } } if(isEndElement()) { if(name() == "subexception") { qDebug()<<"Now at the end of subexception..."; break; } } }}void xml_reader::read_description(){ qDebug()<<"description is: " << readElementText();}void xml_reader::read_duration(){ qDebug()<<"duration is: " << readElementText();}void xml_reader::read_event(){ qDebug()<<"Start to read event..."; while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "id") { read_id(); } if(name() == "offsettime") { read_offsettime(); } if(name() == "eventdesc") { read_eventdesc(); } if(name() == "lasthandle") { read_lasthandle(); } } if(isEndElement()) { if(name() == "event") { qDebug()<<"Now at the end of event.."; break; } } }}void xml_reader::read_offsettime(){ qDebug()<<"offsettime is: " << readElementText();}void xml_reader::read_eventdesc(){ qDebug()<<"Start to read eventdesc..."; while(!atEnd()) { readNext(); if(isStartElement()) { if(name() == "eventname") { read_eventname(); } if(name() == "prompt") { read_prompt(); } } if(isEndElement()) { if(name() == "eventdesc") { qDebug()<<"Now at the end of eventdesc..."; break; } } }}void xml_reader::read_eventname(){ qDebug()<<"eventname is: " << readElementText();}void xml_reader::read_prompt(){ qDebug()<<"prompt is: " << readElementText();}void xml_reader::read_lasthandle(){ qDebug()<<"lasthandle is: " << readElementText();} main.cpp

#include <QtCore/QCoreApplication>#include "XmlPraser.h"int main(int argc, char *argv[]){ QCoreApplication a(argc, argv); QFile file("praser.xml"); XmlPraser reader; if(file.open(QIODevice::ReadOnly | QIODevice::Text)) { qDebug()<<"File has loaded..."; reader.read(&file); } else { qDebug()<<"No file to read..."; } file.close(); qDebug()<<"Press ctrl+C to exit..."; return a.exec();} 

XML文件范例 praser.xml

<?xml version="1.0" encoding="GBK" ?><data><startweek>2010-03-01 00:00:00.000</startweek><eventnumber>2</eventnumber><period><id>223401</id><starttime>2010-03-01 00:00:00.000</starttime><endtime>2010-06-20 23:59:59.999</endtime><exception><subexception><id>01</id><starttime>2010-04-03 00:00:00.000</starttime><endtime>2010-04-05 23:59:59.000</endtime><description>清明节放假三天</description></subexception><subexception><id>02</id><starttime>2010-05-01 00:00:00.000</starttime><endtime>2010-05-03 23:59:59.000</endtime><description>五一劳动节放假三天</description></subexception></exception><duration>0000-00-07 00:00:00.000</duration><event><id>01</id><offsettime>0000-00-00 14:00:00.000</offsettime><eventdesc><eventname>编译原理</eventname><prompt>ring</prompt></eventdesc><lasthandle>null</lasthandle></event><event><id>02</id><offsettime>0000-00-03 09:50:00.000</offsettime><eventdesc><eventname>编译原理</eventname><prompt>vibration</prompt></eventdesc><lasthandle>null</lasthandle></event></period></data> 

 

由于是使用的QXmlStrramReader来进行解析，因而所有的节点都需要自己编写函数进行相应的处理。