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vs2017
rapidxml-1.13

1 RapidXml使用

1.1 创建xml

#include <iostream>
#include "rapidxml/rapidxml.hpp"
#include "rapidxml/rapidxml_utils.hpp"
#include "rapidxml/rapidxml_print.hpp"
using namespace rapidxml;
void crateXml()
{ 

xml_document<> doc;
xml_node<>* rot = doc.allocate_node(rapidxml::node_pi, doc.allocate_string("xml version='1.0' encoding='utf-8'"));
doc.append_node(rot);
xml_node<>* node = doc.allocate_node(node_element, "config", "information");
xml_node<>* color = doc.allocate_node(node_element, "color", NULL);
doc.append_node(node);
node->append_node(color);
color->append_node(doc.allocate_node(node_element, "red", "0.1"));
color->append_node(doc.allocate_node(node_element, "green", "0.1"));
color->append_node(doc.allocate_node(node_element, "blue", "0.1"));
color->append_node(doc.allocate_node(node_element, "alpha", "1.0"));
xml_node<>* size = doc.allocate_node(node_element, "size", NULL);
size->append_node(doc.allocate_node(node_element, "x", "640"));
size->append_node(doc.allocate_node(node_element, "y", "480"));
node->append_node(size);
xml_node<>* mode = doc.allocate_node(rapidxml::node_element, "mode", "screen mode");
mode->append_attribute(doc.allocate_attribute("fullscreen", "false"));
node->append_node(mode);
std::string text;
rapidxml::print(std::back_inserter(text), doc, 0);
std::cout << text << std::endl;
std::ofstream out("config.xml");
out << doc;
}
int main()
{ 

crateXml();
system("PAUSE");
return EXIT_SUCCESS;
}

输出文件config.xml：

<?xml version='1.0' encoding='utf-8' ?>
<config>
<color>
<red>0.1</red>
<green>0.1</green>
<blue>0.1</blue>
<alpha>1.0</alpha>
</color>
<size>
<x>640</x>
<y>480</y>
</size>
<mode fullscreen="false">screen mode</mode>
</config>

1.2 创建xml2

void createXml2()
{ 

xml_document<> doc; //是解析器
char a[] = "<top>"//假设单独传, 就不能加上xml的头部信息，
//否则会报错
"<name>tangqiang</name>"
"<age>22</age>"
"</top>";
char* p = a;
doc.parse<0>(p);
xml_node<>* node = doc.first_node();//去顶级结点
std::cout << (node->name()) << std::endl;
node = node->first_node();
while (node) { 

std::cout << node->name() << ":" << node->value() << std::endl;//name() value()返回的字符串不会去掉首尾的空白字符
node = node->next_sibling();
}
std::ofstream out("test.xml");//ofstream 默认时，假设文件存在则会覆盖原来的内容，不存在则会新建
out << doc;//doc 这样输出时在目标文件里不会有xml 头信息---<?xml version='1.0' encoding='utf-8' >
out.close();
}

输出文件test.xml：

<top>
<name>tangqiang</name>
<age>22</age>
</top>

1.3 读取xml

void readXml()
{ 

file<> fdoc("config.xml");
std::cout << fdoc.data() << std::endl;
xml_document<> doc;
doc.parse<0>(fdoc.data());
std::cout << doc.name() << std::endl;
//! 获取根节点
xml_node<>* root = doc.first_node();
std::cout << root->name() << std::endl;
//! 获取根节点第一个节点
xml_node<>* node1 = root->first_node();
std::cout << node1->name() << std::endl;
xml_node<>* node11 = node1->first_node();
std::cout << node11->name() << std::endl;
std::cout << node11->value() << std::endl;
//! 加入之后再次保存
//须要说明的是rapidxml明显有一个bug
//那就是append_node(doc.allocate_node(node_element,"h","0"));的时候并不考虑该对象是否存在!
xml_node<>* size = root->first_node("size");
size->append_node(doc.allocate_node(node_element, "w", "0"));
size->append_node(doc.allocate_node(node_element, "h", "0"));
std::string text;
rapidxml::print(std::back_inserter(text), doc, 0);
std::cout << text << std::endl;
std::ofstream out("config.xml");
out << doc;
}

输出文件config.xml：

<config>
<color>
<red>0.1</red>
<green>0.1</green>
<blue>0.1</blue>
<alpha>1.0</alpha>
</color>
<size>
<x>640</x>
<y>480</y>
<w>0</w>
<h>0</h>
</size>
<mode fullscreen="false">screen mode</mode>
</config>

1.4 删除节点

void removeNode()
{ 

file<> fdoc("config.xml");
xml_document<> doc;
doc.parse<0>(fdoc.data());
std::string text;
rapidxml::print(std::back_inserter(text), doc, 0);
std::cout << text << std::endl;
xml_node<>* root = doc.first_node();
xml_node<>* sec = root->first_node();
root->remove_node(sec); //移除根节点下的sec结点(包含该结点下全部结点)
text = "删除一个节点\r\n";
rapidxml::print(std::back_inserter(text), doc, 0);
std::cout << text << std::endl;
root->remove_all_nodes(); //移除根节点下全部结点
text = "删除全部节点\r\n";
rapidxml::print(std::back_inserter(text), doc, 0);
std::cout << text << std::endl;
std::ofstream out("test.xml");
out << doc;
}

输出文件test.xml：

<config>
<color>
<red>0.1</red>
<green>0.1</green>
<blue>0.1</blue>
<alpha>1.0</alpha>
</color>
<size>
<x>640</x>
<y>480</y>
<w>0</w>
<h>0</h>
</size>
<mode fullscreen="false">screen mode</mode>
</config>
删除一个节点
<config>
<size>
<x>640</x>
<y>480</y>
<w>0</w>
<h>0</h>
</size>
<mode fullscreen="false">screen mode</mode>
</config>
删除全部节点
<config/>

2 问题记录

2.1 错误 C3861 “print_children”: 找不到标识符

解决方法：
在print_node函数处，rapidxml_print.hpp 104行，前置声明调用到的函数

template<class OutIt, class Ch>
inline OutIt print_children(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_element_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_data_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_cdata_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_declaration_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_comment_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_doctype_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);
template<class OutIt, class Ch>
inline OutIt print_pi_node(OutIt out, const xml_node<Ch>* node, int flags, int indent);

原文连接: https://www.cnblogs.com/rainbow70626/p/10386131.html