Qt之读（解析）XML文件

先上代码

//从config.xml中获取标签appenvironment和oa_app_version的值
//appenvironment值为pro表示生产，为pre表示预生产
QMap<QString, QString> readXml()
{
  QMap<QString, QString> mapList;
  mapList.clear();
  QString configXMLPath = QCoreApplication::applicationDirPath()+"\\config\\config.xml";
  QFile file(configXMLPath);
  if (file.open(QIODevice::ReadOnly | QIODevice::Text))
  {
    QXmlStreamReader reader(&file);
    while (!reader.atEnd() && !reader.hasError())
    {
      QXmlStreamReader::TokenType token = reader.readNext();

      if (token == QXmlStreamReader::StartElement)
      {
        if (reader.name() == "appenvironment" || reader.name() == "oa_app_version")
        {
          QXmlStreamAttributes attributes = reader.attributes();
          if (attributes.hasAttribute("value"))
          {
            QString strValue = attributes.value("value").toString();
            mapList.insert(reader.name().toString(), strValue);
          }
        }
      }
    }
    //解析出错
    if (reader.hasError())
    {
      QString errorInfo = QStringLiteral("XML解析错误：%1  行号：%2  列号：%3  字符位移：%4").
        arg(reader.errorString()).arg(reader.lineNumber()).arg(reader.columnNumber()).arg(reader.characterOffset());
      qDebug() << errorInfo;
    }

    file.close();
    reader.clear();
  }
  return mapList;
}      

这样写，如果是QApplication a(argc, argv);之后调用QMap<QString, QString> readXml()是没有问题的，但是如果要在QApplication a(argc, argv);之前调用QMap<QString, QString> readXml()就会因为QCoreApplication::applicationDirPath()返回为空，导致无法正确解析XML。

//从config.xml中获取标签appenvironment和oa_app_version的值
//appenvironment值为pro表示生产，为pre表示预生产
QMap<QString, QString> readXml()
{
  QMap<QString, QString> mapList;
  mapList.clear();
  TCHAR szPath[MAX_PATH] = { 0 };
  GetModuleFileName(NULL, szPath, MAX_PATH);
  (_tcsrchr(szPath, _T('\\')))[1] = 0;
  QString configXMLPath= QString::fromUtf16((const ushort *)szPath)+"config\\config.xml";
  QFile file(configXMLPath);
  if (file.open(QIODevice::ReadOnly | QIODevice::Text))
  {
    QXmlStreamReader reader(&file);
    while (!reader.atEnd() && !reader.hasError())
    {
      QXmlStreamReader::TokenType token = reader.readNext();

      if (token == QXmlStreamReader::StartElement)
      {
        if (reader.name() == "appenvironment" || reader.name() == "oa_app_version")
        {
          QXmlStreamAttributes attributes = reader.attributes();
          if (attributes.hasAttribute("value"))
          {
            QString strValue = attributes.value("value").toString();
            mapList.insert(reader.name().toString(), strValue);
          }
        }
      }
    }
    //解析出错
    if (reader.hasError())
    {
      QString errorInfo = QStringLiteral("XML解析错误：%1  行号：%2  列号：%3  字符位移：%4").
        arg(reader.errorString()).arg(reader.lineNumber()).arg(reader.columnNumber()).arg(reader.characterOffset());
      qDebug() << errorInfo;
    }

    file.close();
    reader.clear();
  }
  return mapList;
}      

<?xml version="1.0" encoding="UTF-8"?>
<client>
    <app>
        <Appname value="cangege"/>
    </app>
    <server>
        <sdkip value="********" />
        <sdkport value="********" />
        <appid value="********" />
        <client_id value="********" />
        <oa_os_id value="********" />
        <oa_app_version value="1.0.0" /> 
        <appenvironment value="pre" /> <!-- pre(预生产) pro (生产)-->
    </server>
    <loginuser>
         <users id="********"/>
    </loginuser>
</client>