Boost属性树xml解析没有这样的节点()

时间:2016-07-23 12:04:54

标签: c++ xml boost boost-propertytree

我正在尝试使用boost / properties_tree库解析XML文件。我可以正确地获取xml文件和所有内容,但是当我查找孩子时,它找不到任何内容。

我有一个input.xml文件:

<ax:hello someatribute:ax="dwadawfesfjsefs">
    <something>523523</something>
    <ax:whatever>
        <ax:service_tree>
            <ax:service>some</ax:service>
            <ax:url>someulr</ax:url>
        </ax:service_tree>
    </ax:whatever>
</ax:hello>

我尝试解析xml的函数:

void parseXml(std::istream &stream)
{
    using boost::property_tree::ptree;
    ptree pt;
    read_xml(stream, pt);
    BOOST_FOREACH(ptree::value_type const &value, pt.get_child("ax:hello"))
    {
        std::cout << value.first;
    }
}

主要功能:

int main()
{
    std::ifstream stream("input.xml");
    parseXml(stream);
    return 0;
}

我得到的错误信息是:

  

在抛出'boost :: exception_detail :: clone_impl&gt;'的实例后终止调用     what():没有这样的节点(ax:你好)   中止(核心倾销)`

正如您所看到的,ax:hello标记已正确打开和关闭,因此它应该能够找到它而不管属性,对吗?

希望有人知道这里发生了什么!

1 个答案:

答案 0 :(得分:2)

您正在做其他错误/不同的事情:

<强> Live On Coliru

#include <iostream>
#include <fstream>
#include <boost/property_tree/xml_parser.hpp>
#include <boost/foreach.hpp>

void parseXml(std::istream &stream)
{
    using boost::property_tree::ptree;
    ptree pt;
    read_xml(stream, pt);
    BOOST_FOREACH(ptree::value_type const &value, pt.get_child("ax:hello"))
    {
        std::cout << value.first << "\n";
    }
}

int main()
{
    std::istringstream stream(R"(
        <ax:hello someatribute:ax="dwadawfesfjsefs">
            <something>523523</something>
            <ax:whatever>
                <ax:service_tree>
                    <ax:service>some</ax:service>
                    <ax:url>someulr</ax:url>
                </ax:service_tree>
            </ax:whatever>
        </ax:hello>
)");
    parseXml(stream);
}

打印

<xmlattr>
something
ax:whatever

稍微复杂的倾销:

void dump(ptree const& pt, std::string const& indent = "") {
    for (auto& node : pt) {
        std::cout << indent << node.first;
        auto value = boost::trim_copy(node.second.get_value(""));
        if (!value.empty())
            std::cout << ": '" << value << "'";
        std::cout << "\n";
        dump(node.second, indent + "    ");
    }
}

打印 Live On Coliru

ax:hello
    <xmlattr>
        someatribute:ax: 'dwadawfesfjsefs'
    something: '523523'
    ax:whatever
        ax:service_tree
            ax:service: 'some'
            ax:url: 'someulr'