XML read/write using XMLLite.

xmlrw.cpp

#include<iostream>
#include<string>
#include<xmllite.h>
#include<atlmem.h>
#include<Shlwapi.h>
#pragma comment(lib,"xmllite.lib")
#pragma comment(lib,"shlwapi.lib")
struct HResultBase
{
	HResultBase() :result(S_OK) {}
	HResultBase(const HRESULT &_hr) :result(_hr) { Check(); }
	virtual HRESULT operator=(const HRESULT &_hr)
	{
		result = _hr;
		Check();
		return Get();
	}
	bool operator==(const HRESULT &_hr) { return result == _hr; }
	bool operator!=(const HRESULT &_hr) { return !operator==(_hr); }
	virtual HRESULT Get()
	{
		return result;
	}
protected:
	virtual void Check()
	{
		if (FAILED(result))
			std::cerr << "发生错误：" << result << std::endl;
	}
	HRESULT result;
};
struct HResultWriter:public HResultBase
{
	HResultWriter(const HRESULT &_hr) :HResultBase(_hr) {}
	HRESULT operator=(const HRESULT &_hr)
	{
		return HResultBase::operator=(_hr);
	}
};
struct HResultReader :public HResultBase
{
	HResultReader(const HRESULT &_hr) :HResultBase(_hr) {}
	HRESULT operator=(const HRESULT &_hr)
	{
		result = _hr;
		if (result == S_FALSE)
			std::clog << "不存在属性。" << std::endl;
		else Check();
		return result;
	}
};

//读取节点的属性
HRESULT DisplayAttributes(IXmlReader* pReader)
{
	const WCHAR* pwszPrefix, *pwszLocalName, *pwszValue;
	HResultReader hr = pReader->MoveToFirstAttribute();//跳到第一个属性，函数返回S_FALSE没有属性，其他的就应该是失败了

	if (hr == S_FALSE)return hr.Get();//没有直接跳出
	if (hr != S_OK)//失败，打印失败信息，不过我都一般会加上失败的位置
		return hr.Get();
	else
	{
		do
		{
			if (!pReader->IsDefault())
			{
				UINT cwchPrefix;
				hr = pReader->GetPrefix(&pwszPrefix, &cwchPrefix);//获得节点命名空间的前缀
				hr = pReader->GetLocalName(&pwszLocalName, NULL);//获取属性名称
				hr = pReader->GetValue(&pwszValue, NULL);//获取属性值
				if (cwchPrefix > 0)//分两种情况输出 有前缀和没有前缀
					wprintf(L"Attr: %s:%s=\"%s\" \n", pwszPrefix, pwszLocalName, pwszValue);
				else
					wprintf(L"Attr: %s=\"%s\" \n", pwszLocalName, pwszValue);
			}
		} while (S_OK == pReader->MoveToNextAttribute());//移动到下一个属性
	}
	return hr.Get();
}
int main()
{
	std::string strSection, strKey, strValue;
	const TCHAR strFile[] = TEXT("settings.xml"), strUpdateFile[] = TEXT("update.xml");
	CComPtr<IStream> pFileStream;
	CComPtr<IXmlReader> pReader;
	CComPtr<IXmlWriter> pWriter;
	HResultWriter hrw = S_OK;
	HResultReader hrr = S_OK;
	std::cerr.setf(std::ios::right | std::ios::hex);
	hrw = CreateXmlWriter(__uuidof(IXmlWriter), (void**)&pWriter, nullptr);//创建xmlWriter
	hrr = CreateXmlReader(__uuidof(IXmlReader), (void**)&pReader, nullptr);
	hrw = pWriter->SetProperty(XmlWriterProperty_Indent, TRUE);//设置xmlWriter属性
	
	hrw = SHCreateStreamOnFile(strUpdateFile, STGM_CREATE | STGM_READWRITE, &pFileStream);
	hrw = pWriter->SetOutput(pFileStream);
	hrw = pWriter->WriteStartDocument(XmlStandalone_Omit);//写xml文件头
	
	hrw = pWriter->WriteStartElement(NULL, TEXT("Update"), NULL);

	hrw = pWriter->WriteElementString(NULL, TEXT("Version"), NULL, TEXT("1.0.0.1"));
	hrw = pWriter->WriteElementString(NULL, TEXT("PatchURL"), NULL, TEXT("https://github.com/lxfly2000"));
	hrw = pWriter->WriteElementString(NULL, TEXT("DownloadURL"), NULL, TEXT("http://blog.sina.com/lxfly2000"));
	hrw = pWriter->WriteElementString(NULL, TEXT("ReleasePage"), NULL, TEXT("http://blog.sina.com/lxfly2000"));
	
	hrw = pWriter->WriteEndElement();

	hrw = pWriter->WriteEndDocument();
	hrw = pWriter->Flush();
	pFileStream.Release();

	hrw = SHCreateStreamOnFile(strFile, STGM_CREATE | STGM_READWRITE, &pFileStream);//创建输出流
	hrw = pWriter->SetOutput(pFileStream);//绑定输出流
	hrw = pWriter->WriteStartDocument(XmlStandalone_Omit);//写xml文件头
	//hrw = pWriter->WriteDocType(L"XML", NULL, NULL, NULL);//如果写上这句会在读的时候出一些问题
	
	hrw = pWriter->WriteStartElement(NULL, TEXT("KaikiSettings"), NULL);

	hrw = pWriter->WriteStartElement(NULL, TEXT("Joy"), NULL);
	hrw = pWriter->WriteElementString(NULL, TEXT("Up"), NULL, TEXT("12"));
	hrw = pWriter->WriteEndElement();

	hrw = pWriter->WriteStartElement(NULL, TEXT("Program"), NULL);
	hrw = pWriter->WriteElementString(NULL, TEXT("IsFullScreen"), NULL, TEXT("True"));
	hrw = pWriter->WriteElementString(NULL, TEXT("IsDeveloper"), NULL, TEXT("False"));
	hrw = pWriter->WriteEndElement();

	hrw = pWriter->WriteEndElement();
	
	hrw = pWriter->WriteEndDocument();
	hrw = pWriter->Flush();

	hrr = pFileStream->Seek({ 0i64 }, STREAM_SEEK_SET, NULL);

	XmlNodeType nodeType;
	const WCHAR* pwszPrefix, *pwszLocalName, *pwszValue;
	UINT cwchPrefix;

	//Open read-only input stream
	//hrr = SHCreateStreamOnFile(strFile, STGM_READ, &pFileStream);//创建输入流
	//hrr = CreateXmlReader(__uuidof(IXmlReader), (void**)&pReader, NULL);//创建XmlReader
	hrr = pReader->SetProperty(XmlReaderProperty_DtdProcessing, DtdProcessing_Prohibit);//设置XmlReader的属性
	hrr = pReader->SetInput(pFileStream);//将输入流绑定到XmlReader

	//read until there are no more nodes
	while (S_OK == (hrr = pReader->Read(&nodeType)))//循环 每次往前走一步 
	{
		switch (nodeType)
		{
		case XmlNodeType_XmlDeclaration://如果是声明
			wprintf(L"XmlDeclaration\n");
			hrr = DisplayAttributes(pReader);
			break;
		case XmlNodeType_Element://如果是开始节点
			hrr = pReader->GetPrefix(&pwszPrefix, &cwchPrefix);//获取节点前缀
			hrr = pReader->GetLocalName(&pwszLocalName, NULL);//获取节点名称
			if (cwchPrefix > 0)//分 有前缀和没有前缀两种情况输出
				wprintf(L"Element: %s:%s\n", pwszPrefix, pwszLocalName);
			else
				wprintf(L"Element: %s\n", pwszLocalName);
			hrr = DisplayAttributes(pReader);//输出节点属性
			//hrr = pReader->MoveToElement();//要从属性 跳回到 节点
			if (pReader->IsEmptyElement())//空的节点
				wprintf(L" (empty)");
			break;
		case XmlNodeType_EndElement://关闭节点
			hrr = pReader->GetPrefix(&pwszPrefix, &cwchPrefix);
			hrr = pReader->GetLocalName(&pwszLocalName, NULL);//关闭节点的名称
			if (cwchPrefix > 0)
				wprintf(L"End Element: %s:%s\n", pwszPrefix, pwszLocalName);
			else
				wprintf(L"End Element: %s\n", pwszLocalName);
			break;
		case XmlNodeType_Text://值
			hrr = pReader->GetValue(&pwszValue, NULL);//获取值
			wprintf(L"Text: %s\n", pwszValue);
		case XmlNodeType_Whitespace://这个其实是回车，我自己发现的
			break;
		case XmlNodeType_CDATA://这几个类型我没有用到
			hrr = pReader->GetValue(&pwszValue, NULL);
			wprintf(L"CDATA: %s\n", pwszValue);
			break;
		case XmlNodeType_ProcessingInstruction:
			hrr = pReader->GetLocalName(&pwszLocalName, NULL);
			hrr = pReader->GetValue(&pwszValue, NULL);
			wprintf(L"Processing Instruction name:%s value:%s\n", pwszLocalName, pwszValue);
			break;
		case XmlNodeType_Comment:
			hrr = pReader->GetValue(&pwszValue, NULL);
			wprintf(L"Comment: %s\n", pwszValue);
			break;
		case XmlNodeType_DocumentType:
			wprintf(L"DOCTYPE is not printed\n");
			break;
		}
	}

	pReader.Release();
	pWriter.Release();
	pFileStream.Release();
	return 0;
}