使用rapidxml 生成xml文件[通俗易懂]

大家好，又见面了，我是你们的朋友全栈君。

      rapidxml是一个快速的xml库，由C++模板实现的高效率xml解析库，同时也是boost库的property_tree的内置解析库。

     当时rapidxml时，只需要把rapidxml.hpp 、 rapidxml_print.hpp 和 rapidxml_utils.hpp 三个文件拷贝到你的工程目录下，就可以了。

下面的是测试代码 main.cpp

#include <iostream>
#include <string>
#include <vector>
#include "rapidxml/rapidxml.hpp"
#include "rapidxml/rapidxml_print.hpp"
#include "rapidxml/rapidxml_utils.hpp"

using namespace std;

int main(int argc, char** argv) {
	vector<string>  v_str ;
	vector<string>::iterator it ;
	v_str.push_back("111111");
	v_str.push_back("222222");
	v_str.push_back("333333");
	v_str.push_back("444444");

	using namespace rapidxml;
	xml_document<> doc;  //构造一个空的xml文档
	xml_node<>* rot = doc.allocate_node(rapidxml::node_pi, doc.allocate_string("setting.xml version='1.0' encoding='utf-8'"));//allocate_node分配一个节点，该节点类型为node_pi，对XML文件进行描，描述内容在allocate_string中
	doc.append_node(rot); //把该节点添加到doc中

	xml_node<>* node = doc.allocate_node(node_element, "root", NULL）；

	xml_node<>* analysis = doc.allocate_node(node_element, "Analysis", NULL);
	node->append_node(analysis);
	for (it = v_str.begin(); it != v_str.end(); it++) {
		xml_node<>* soinfo = doc.allocate_node(node_element, "soinfo", NULL);
		soinfo->append_attribute(doc.allocate_attribute("key", it->c_str()));
		analysis->append_node(soinfo);
	}

	xml_node<>* Output = doc.allocate_node(node_element, "Output", NULL);
	node->append_node(Output);

	xml_node<>* outinfo = doc.allocate_node(node_element, "outinfo", NULL);
	Output->append_node(outinfo);
	for (int j =0;j < 2; j++) {
		xml_node<>* type = doc.allocate_node(node_element, "desc", NULL); //分配一个type节点，
		type->append_attribute(doc.allocate_attribute("path", "123"));
		type->append_attribute(doc.allocate_attribute("relation", "345"));
		type->append_attribute(doc.allocate_attribute("priority", "567"));
		outinfo->append_node(type); //把type节点添加到节点outinfo中
	}

	for (it = v_str.begin(); it != v_str.end(); it++) {
		xml_node<>* rule = doc.allocate_node(node_element, "rule", NULL);
		Output->append_node(rule);
		for (int i = 0; i < 2 ; i++) {
			xml_node<>* cond = doc.allocate_node(node_element, "cond", NULL);
			cond->append_attribute(doc.allocate_attribute("key", "123"));
			cond->append_attribute(doc.allocate_attribute("value", "345"));
			cond->append_attribute(doc.allocate_attribute("relation","567"));
			rule->append_node(cond);
		}
		xml_node<>* out = doc.allocate_node(node_element, "out", NULL);
		out->append_attribute(doc.allocate_attribute("where", it->c_str()));
		rule->append_node(out);
	}

	doc.append_node(node);
	std::ofstream pout("config.xml");
	pout << doc;
	return 0;
}

下面是生成的xml文件 config.xml

<?setting.xml version='1.0' encoding='utf-8' ?>
<root>
	<Analysis>
		<soinfo key="111111"/>
		<soinfo key="222222"/>
		<soinfo key="333333"/>
		<soinfo key="444444"/>
	</Analysis>
	<Output>
		<outinfo>
			<desc path="123" relation="345" priority="567"/>
			<desc path="123" relation="345" priority="567"/>
		</outinfo>
		<rule>
			<cond key="123" value="345" relation="567"/>
			<cond key="123" value="345" relation="567"/>
			<out where="111111"/>
		</rule>
		<rule>
			<cond key="123" value="345" relation="567"/>
			<cond key="123" value="345" relation="567"/>
			<out where="222222"/>
		</rule>
		<rule>
			<cond key="123" value="345" relation="567"/>
			<cond key="123" value="345" relation="567"/>
			<out where="333333"/>
		</rule>
		<rule>
			<cond key="123" value="345" relation="567"/>
			<cond key="123" value="345" relation="567"/>
			<out where="444444"/>
		</rule>
	</Output>
</root>