tinyxml

github下载相关的软件包，其中有四个文件需要主要需要关注就是分别是tinyxml12.cpp，tinyxml12.h，rss网页xml文件，还有就是官方给的test文件tinyxmltest.cpp。

example1就是提供一个打开文件的方式

int example_1()
{XMLDocument doc;doc.LoadFile( "resources/dream.xml" );return doc.ErrorID();
}

example3就是处理一个字符串

int example_3()
{static const char* xml ="<?xml version=\"1.0\"?>""<!DOCTYPE PLAY SYSTEM \"play.dtd\">""<PLAY>""<TITLE>A Midsummer Night's Dream</TITLE>""</PLAY>";XMLDocument doc;doc.Parse( xml );//可能需要注意这个地方读取文件以后也可以直接使用XMLElement* titleElement = doc.FirstChildElement( "PLAY" )->FirstChildElement( "TITLE" );const char* title = titleElement->GetText();printf( "Name of play (1): %s\n", title );XMLText* textNode = titleElement->FirstChild()->ToText();title = textNode->Value();printf( "Name of play (2): %s\n", title );return doc.ErrorID();
}

最后在编译的时候记得gcc test.cc tinyxml.cc 进行联合编译，要不然的话不能知道相关的在hpp中的函数定义在什么位置。

然后就可以借助于regex函数借助于正则表达式处理字符串文件

可以从c++参考文档中正则表达式获得

#include <iostream>
#include <iterator>
#include <regex>
#include <string>int main()
{std::string text = "Quick brown fox";std::regex vowel_re("a|e|i|o|u");// 写结果到输出迭代器std::regex_replace(std::ostreambuf_iterator<char>(std::cout),text.begin(), text.end(), vowel_re, "*");// 构造保有结果的字符串std::cout << '\n' << std::regex_replace(text, vowel_re, "[$&]") << '\n';
}//输出结果
Q**ck br*wn f*x
Q[u][i]ck br[o]wn f[o]x

当然在下面的文档中是通过gpt获得的一种替换方法

#include "tinyxml2.h"
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <regex>
using std::cout;
using std::endl;
using std::string;
using std::vector;
using std::ofstream;
using std::regex;
using tinyxml2::XMLDocument;
using tinyxml2::XMLElement;
using tinyxml2::XMLText;struct RssItem
{string title;string link;string description;string content;
};class RssReader
{
public:RssReader(int size){_rss.reserve(size);}//使用string类型也可以接收char*类型//如果使用char*类型的不能接收string类型int parseRss(const char * filename){XMLDocument doc;if(doc.LoadFile(filename) != tinyxml2::XML_SUCCESS){//实际上这是一个enum定义数值是0，所以只需要返回值不为0的时候就可以cout << "doc open error! " << endl;return 1;}for (tinyxml2::XMLElement* titleElement = doc.FirstChildElement("rss")>FirstChildElement("channel")->FirstChildElement("item"); titleElement; titleElement = titleElement->NextSiblingElement("item")) {//这个地方主要是用到nextsibingElement用来访问下一个节点struct RssItem rss;//获取title内容XMLElement * element = titleElement->FirstChildElement("title");if(element){const char* title = element->GetText();rss.title = title;}element = titleElement->FirstChildElement("link");if(element){const char * link = element->GetText();rss.link = link;}element = titleElement->FirstChildElement("description");if(element){const char * description= element->GetText();rss.description = description;}element = titleElement->FirstChildElement("content:encoded");if(element){const char * content= element->GetText();rss.content = content;}_rss.push_back(rss);}//解析return 0;}void dump(const string & filename){ofstream ofs(filename.c_str());int cnt = 1;while(!_rss.empty()){ofs << "<doc>" << endl;ofs << "    " <<"<docid>" << cnt++ << "</docid>" << endl;RssItem rss;rss = _rss.front();regex pattern("<.*?>");string replacement = "";string result = regex_replace(rss.title, pattern, replacement);ofs << "    " << "<title>" << result << "</title>" <<endl;result = regex_replace(rss.link, pattern, replacement);ofs << "    " << "<link>" << result << "</link>" <<endl;result = regex_replace(rss.description, pattern, replacement);ofs << "    " << "<description>" << result << "</description>" <<endl;result = regex_replace(rss.content, pattern, replacement);ofs << "    " << "<content>" << result << "</content>" <<endl;_rss.pop_back();}ofs.close();}//输出
private:vector<RssItem> _rss;
};   int main()
{RssReader rs(10);rs.parseRss("feed.txt");rs.dump("content.txt");return 0;
}