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。

此时可以调用Windows API，如下所示。

//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> 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格式如下。

<?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>