TinyXML2 创建及操作XML文件

TinyXML2 下载地fhg :
https://github.com/leethomason/tinyxml2

使用方法:
将.h.cpp 放至工程中,
然后 引用

#include"tinyxml2.h"
using namespace tinyxml2;

即可

---

以如下XML文件格式进行解析:

<频率名称列表>
    <测试>
        <起始频率>555起始频率>
        <终止频率>555终止频率>
        <步进>555步进>
    测试>
频率名称列表>

操作类:

#pragma once

#include 

#include"tinyxml2.h"
using namespace tinyxml2;

class FreqDataXml final
{
public:
	FreqDataXml();
	~FreqDataXml();

public:
	void init();
	
	void readXml();

	XMLElement* queryrNodeByName(const QString& strNodeName);

	bool insertNode(QString strName, float dS, float dE, float dStep);
	bool modifyNode(XMLElement* pNode, QString strName, float dS, float dE, float dStep);

	bool delNode(XMLElement* pNode);

	bool getNodeFreqInfo(XMLElement* pNode, float& dS, float& dE, float& dStep);

	void save();

private:
	void createXml();


private:
	QString m_strFileName;
	XMLDocument	m_doc;
	XMLElement*		m_pRoot = nullptr;
};

---

#include "FreqDataXml.h"

#include 
#include 
#include 

FreqDataXml::FreqDataXml()
{
	init();
}


FreqDataXml::~FreqDataXml()
{
	//save();
}


void FreqDataXml::init()
{
	m_strFileName = QCoreApplication::applicationDirPath() + "/freqdata.xml";

	QFile file(m_strFileName);
	if (!file.exists())	// 文件不存在
	{
		createXml();
	}
	else
	{
		tinyxml2::XMLError ret = m_doc.LoadFile(m_strFileName.toLocal8Bit().data());
		if (XML_SUCCESS != ret)
		{
			// 文件错误, 删除
			QFile fileTemp(m_strFileName);
			fileTemp.remove();
			m_doc.Clear();
			return;
		}

		m_pRoot = m_doc.RootElement();
		qDebug() << QString::fromLocal8Bit(m_pRoot->Name());
	}
}

/*  创建后的文件如下:
	< ? xml version = "1.0" encoding = "UTF-8" ? >
		<频率名称列表>
		< / 频率名称列表>
*/
void FreqDataXml::createXml()
{
	const char* declaration = "";
	m_doc.Parse(declaration);//会覆盖xml所有内容

	m_pRoot = m_doc.NewElement("频率名称列表");
	m_doc.InsertEndChild(m_pRoot);


	//XMLElement* freq = m_doc.NewElement("航空");
	//m_pRoot->InsertEndChild(freq);

	//tinyxml2::XMLElement* freqS = m_doc.NewElement("起始频率");
	//tinyxml2::XMLText* value = m_doc.NewText("68.9");
	//freq->InsertEndChild(freqS);
	//freqS->InsertEndChild(value);

	//tinyxml2::XMLElement* freqE = m_doc.NewElement("终止频率");
	//freq->InsertEndChild(freqE);
	//value = m_doc.NewText("89.6");
	//freqE->InsertEndChild(value);

	//tinyxml2::XMLElement* freqStep = m_doc.NewElement("终止频率");
	//freq->InsertEndChild(freqStep);
	//value = m_doc.NewText("25");
	//freqStep->InsertEndChild(value);

}

void FreqDataXml::readXml()
{
	XMLElement* pNode = m_pRoot->FirstChildElement();
	XMLElement* pSubNode = nullptr;
	while (pNode)
	{
		// 频率名称
		qDebug() << "\n";
		const char* pName = pNode->Value();
		qDebug() << QString::fromLocal8Bit(pName);

		// 起始频率
		pSubNode = pNode->FirstChildElement();
		pName = pSubNode->Value();
		qDebug() << QString::fromLocal8Bit(pName);
		// 起始频率 值
		pName = pSubNode->GetText();
		qDebug() << QString::fromLocal8Bit(pName);

		// 终止频率
		pSubNode = pSubNode->NextSiblingElement();
		pName = pSubNode->Value();
		qDebug() << QString::fromLocal8Bit(pName);
		// 终止频率 值
		pName = pSubNode->GetText();
		qDebug() << QString::fromLocal8Bit(pName);

		// 步进
		pSubNode = pSubNode->NextSiblingElement();
		pName = pSubNode->Value();
		qDebug() << QString::fromLocal8Bit(pName);
		// 步进 值
		pName = pSubNode->GetText();
		qDebug() << QString::fromLocal8Bit(pName);

		pNode = pNode->NextSiblingElement();
	}
}

tinyxml2::XMLElement* FreqDataXml::queryrNodeByName(const QString& strNodeName)
{
	XMLElement*    pNode = m_pRoot->FirstChildElement();
	XMLElement*    pSubNode = nullptr;
	while (pNode)
	{
		qDebug() << "\n";
		const char* pName = pNode->Value();

		if (0 == strNodeName.compare(QString::fromLocal8Bit(pName), Qt::CaseInsensitive))
			return pNode;

		pNode = pNode->NextSiblingElement();
	}

	return nullptr;
}

bool FreqDataXml::insertNode(QString strName, float dS, float dE, float dStep)
{
	XMLElement* nodeName = m_doc.NewElement(strName.toLocal8Bit().constData());
	m_pRoot->InsertEndChild(nodeName);

	XMLElement* nodeStartFreq = m_doc.NewElement("起始频率");
	nodeStartFreq->SetText(dS);
	nodeName->InsertEndChild(nodeStartFreq);

	XMLElement* nodeEndFreq = m_doc.NewElement("终止频率");
	nodeEndFreq->SetText(dE);
	nodeName->InsertEndChild(nodeEndFreq);

	XMLElement* nodeStepFreq = m_doc.NewElement("步进");
	nodeStepFreq->SetText(dStep);
	nodeName->InsertEndChild(nodeStepFreq);

	return true;
}

bool FreqDataXml::modifyNode(XMLElement* pNode, QString strName, float dS, float dE, float dStep)
{
	if (!pNode)
		return false;

	pNode->SetName(strName.toLocal8Bit().constData());
	//pNode->SetText(strName.toLocal8Bit().constData());

	pNode = pNode->FirstChildElement();
	pNode->SetText(dS);

	pNode = pNode->NextSiblingElement();
	pNode->SetText(dE);

	pNode = pNode->NextSiblingElement();
	pNode->SetText(dStep);
}

bool FreqDataXml::delNode(XMLElement* pNode)
{
	if (!pNode)
		return false;

	m_pRoot->DeleteChild(pNode);
	return true;
}

bool FreqDataXml::getNodeFreqInfo(XMLElement* pNode, float& dS, float& dE, float& dStep)
{
	if (!pNode)
		return false;

	pNode = pNode->FirstChildElement();
	dS = atof(pNode->GetText());

	pNode = pNode->NextSiblingElement();
	dE = atof(pNode->GetText());

	pNode = pNode->NextSiblingElement();
	dStep = atof(pNode->GetText());

	return true;
}

void FreqDataXml::save()
{
	m_doc.SaveFile(m_strFileName.toLocal8Bit().data());
}

---

使用

FreqDataXml  freq;

		freq.insertNode(QString::fromLocal8Bit("如同太陽"), 33.2f, 33.3f, 22.2f);
		freq.insertNode(QString::fromLocal8Bit("定文件"), 3254.99f, 232.52f, 54.6f);
		freq.insertNode(QString::fromLocal8Bit("删除"),  54.6f, 335.3f, 222.2f);
		freq.insertNode(QString::fromLocal8Bit("源码库"), 324.2f, 83.3f, 12.2f);
		freq.readXml();

		
		XMLElement* pNode = freq.queryrNodeByName(QString::fromLocal8Bit("删除"));

		
		float dS;
		float dE;
		float dStep;

		freq.getNodeFreqInfo(pNode, dS, dE, dStep);
		qDebug() << dS << "\t" << dE << "\t" << dStep;

		pNode = freq.queryrNodeByName(QString::fromLocal8Bit("删除"));
		freq.modifyNode(pNode, QString::fromLocal8Bit("删除x"), 11.1f, 22.2f, 33.3f);

		pNode = freq.queryrNodeByName(QString::fromLocal8Bit("删除"));
		freq.getNodeFreqInfo(pNode, dS, dE, dStep);
		qDebug() << dS << "\t" << dE << "\t" << dStep;

		freq.save();
		```