最近需要在c++引擎中使用xml解析及生成功能，对选择xml库的过程记录一下
xml benchmark
- 参考 XML Benchmark Results 10.10.2009 的结果 初步选择使用RapidXML
- 查看RapidXML自己的benchmark数据，性能接近strlen
使用示例
参考各种数据对比，决定使用RapidXML，解析及生成的示例代码如下
#include <iostream>
#include <string>
#include <vector>
#include <sstream> // for stringstream
#include "rapidxml.hpp"
#include "rapidxml_print.hpp"
using namespace std;
void parse() {
string s =
"<xml4nlp>"
"<doc scribbleList=\"\" nid=\"001\" scribble=\"0\" length=\"5\">"
"<para id=\"0\" offset=\"0\">"
"<sent id=\"0\" cont=\"apple\">"
"<word id=\"0\" cont=\"apple\" pos=\"n\" ne=\"O\" head=\"2\" relation=\"ATT\"/>"
"</sent>"
"</para>"
"</doc>"
"</xml4nlp>";
vector<char> xml(s.begin(), s.end());
xml.emplace_back('\0');
rapidxml::xml_document<> xml_doc;
try {
xml_doc.parse<rapidxml::parse_default>(xml.data());
auto dump_attribute = [](rapidxml::xml_node<> * node) {
for (rapidxml::xml_attribute<> * attribute = node->first_attribute(); attribute; attribute = attribute->next_attribute()) {
std::cout << " attribute name=" << attribute->name() << " value=" << attribute->value() << endl;
}
};
rapidxml::xml_node<>* xml4nlp = xml_doc.first_node("xml4nlp");
for (rapidxml::xml_node<> * doc = xml4nlp->first_node("doc"); doc; doc = doc->next_sibling()) {
for (rapidxml::xml_node<>* para = doc->first_node("para"); para; para = para->next_sibling()) {
for (rapidxml::xml_node<>* sent = para->first_node("sent"); sent; sent = sent->next_sibling()) {
for (rapidxml::xml_node<>* word = sent->first_node("word"); word; word = word->next_sibling()) {
dump_attribute(word);
}
}
}
}
}
catch (rapidxml::parse_error e) {
std::cout << e.what() << std::endl;
}
}
void generate() {
// 1.DOM
rapidxml::xml_document<> doc;
// 2.node_declaration
rapidxml::xml_node<>* declaration = doc.allocate_node(rapidxml::node_declaration);
declaration->append_attribute(doc.allocate_attribute("version", "1.0"));
declaration->append_attribute(doc.allocate_attribute("encoding", "utf-8"));
doc.append_node(declaration);
// 3.node_element
rapidxml::xml_node<>* root = doc.allocate_node(rapidxml::node_element, "xml4nlp");
doc.append_node(root);
// 4.node_comment
rapidxml::xml_node<>* comment = doc.allocate_node(rapidxml::node_comment, 0, "This is a node for comment!");
root->append_node(comment);
rapidxml::xml_node<>* para = doc.allocate_node(rapidxml::node_element, "para");
root->append_node(para);
// 5.set attribute
rapidxml::xml_node<>* sent = doc.allocate_node(rapidxml::node_element, "sent");
para->append_node(sent);
sent->append_attribute(doc.allocate_attribute("id", doc.allocate_string("0")));
sent->append_attribute(doc.allocate_attribute("cont", doc.allocate_string("apple")));
stringstream output;
output << doc;
cout << output.str() << endl;
}
int main(int argc, char** argv) {
parse();
//generate();
return 0;
}
Reference
