关于XML标签中的键值该如何解析？

[lamliukang]

<library name="UESTC library"> <book id="1234" language="en" edition="1"> <title>Harry Potter and the Philosopher's Stone</title> <author>J.K. Rowling</author> </book> </library>
对于标签或者，我需要解析name字段，也就是值"UESTC library"，将值保存到结构体的name成员中，我需要如何设置我的结构体？

[qicosmos]

1. 通过attr() 拿到属性值：

struct book_t {
  std::string title;
  std::string author;
};
REFLECTION(book_t, title, author);
struct library {
  iguana::xml_attr_t<book_t> book;
};
REFLECTION(library, book);

void lib_example() {
  std::string str = R"(
  <library name="UESTC library">
    <book id="1234" language="en" edition="1">
      <title>Harry Potter and the Philosopher's Stone</title>
      <author>J.K. Rowling</author>
      </book>
  </library>
)";
  {
    iguana::xml_attr_t<library> lib;
    iguana::from_xml(lib, str);

    auto attr = lib.attr();
    for (auto [k, v] : attr) {
      std::cout << k << ": " << v << "\n";
    }
  }

将会打印出属性名字和值：name: UESTC library

2. 通过attr()去修改或者增加属性

  {
    iguana::xml_attr_t<library> lib;
    lib.attr().emplace("name", "tom");

    iguana::xml_attr_t<book_t> book;
    book.attr()["id"] = "42";
    book.attr().emplace("language", "cn");

    book.value().author = "tom";
    book.value().title = "a story";
    lib.value().book = book;

    std::string str;
    iguana::to_xml<true>(lib, str);
    std::cout << str << "\n";
  }

将会打印：

<library name="tom">
	<book language="cn" id="42">
		<title>a story</title>
		<author>tom</author>
	</book>
</library>