我尝试使用我的程序cpp解析XML文件,并将其存储在QList上,但我不知道为什么当我执行代码时应用程序不返回任何内容(有时单独关闭)
这是我的功能:
void mission::loadMission(QList < waypoint* > wpList , QString filename){
QXmlStreamReader xmlReader;
int i=0 ;
QFile file(filename);
if(file.open(QIODevice::ReadOnly)) {
xmlReader.setDevice(&file);;
xmlReader.readNext();
xmlReader.readNext();
bool ok = false ;
//Reading from the file
while (!xmlReader.isEndDocument())
{
if (xmlReader.isStartElement())
{
QString name = xmlReader.name().toString();
if (name == "Number" )
{
wpList[i]->setNum(xmlReader.readElementText().toInt(&ok,10));
}
else if (name == "Longitude" )
{
wpList[i]->setLong(xmlReader.readElementText().toDouble(&ok));
}
else if (name == "Latitude" )
{
wpList[i]->setLat(xmlReader.readElementText().toDouble(&ok));
}
else if (name == "Altitude" )
{
wpList[i]->setAlt(xmlReader.readElementText().toDouble(&ok));
}
else if (name == "Heading" )
{
wpList[i]->setHdg(xmlReader.readElementText().toDouble(&ok));
}
else if (name == "Time" )
{
wpList[i]->setTime(xmlReader.readElementText().toInt(&ok,10));
}
else if (name == "Type" )
{
wpList[i]->setType(xmlReader.readElementText().toInt(&ok,10));
}
}
else if (xmlReader.isEndElement())
{
xmlReader.readNext();
i++ ;
}
}
if (xmlReader.hasError())
{
cout << "XML error: " << xmlReader.errorString().data() << std::endl;
}
}
}
这是我的XML文件的例子:
<?xml version="1.0" encoding="UTF-8"?>
<Mission>
<Number>2013_7_11_16_28</Number>
<Waypoint>
<Number>0</Number>
<Longitude>1.26946</Longitude>
<Latitude>43.5147</Latitude>
<Altitude>100</Altitude>
<Heading>90</Heading>
<Time>4400</Time>
<Type>1</Type>
</Waypoint>
<Waypoint>
<Number>1</Number>
<Longitude>1.56958</Longitude>
<Latitude>43.4721</Latitude>
<Altitude>100</Altitude>
<Heading>90</Heading>
<Time>4400</Time>
<Type>1</Type>
</Waypoint>
<Waypoint>
<Number>2</Number>
<Longitude>1.64424</Longitude>
<Latitude>43.655</Latitude>
<Altitude>100</Altitude>
<Heading>90</Heading>
<Time>4400</Time>
<Type>1</Type>
</Waypoint>
</Mission>
答案 0 :(得分:1)
我建议你继续使用常规C ++&amp; STL,然后当你更精通时继续前进到Qt。我注意到的一些事情是关于基本的C ++编程,并且与Qt无关。
对于初学者,需要通过引用而不是值传递。
void mission::loadMission(QList<waypoint*> &wpList , QString filename){
// ...
}
通过存储指针的QList可能几乎没有什么好处。我也只有QList&lt;航点&GT; &放;.然后使用QList :: push_back()方法并填充列表,而不是试图猜测列表的索引位置。
void mission::loadMission(QList<waypoint> &wpList , QString filename){
// ...
QStringRef name = xmlReader.name();
if (name == "Waypoint" )
{
waypoint wp;
wpList.push_back(wp);
}
if (name == "Number" )
{
wpList.back().setNum(xmlReader.readElementText().toInt(&ok,10));
}
也无需从QStringRef
制作QString的临时副本 QStringRef name = xmlReader.name();
if (name == "Number" )
{ // ...
}