c++ - 将子树添加到 boost::property_tree 元素

Question

我想要的是这样的:

<tree>
    <objects>
        <object id="12345678">
            <AdditionalInfo>
                <Owner>Mr. Heik</Owner>
                <Health>37/100</Health>
            </AdditionalInfo>
        </object>
    </objects>
</tree>

我得到的是这样的:

<tree>
    <objects>
        <object id="12345678"/>
        <AdditionalInfo>
            <Owner>Mr. Heik</Owner>
            <Health>37/100</Health>
        </AdditionalInfo>
    </objects>
</tree>

我尝试的是这样的:

using boost::property_tree::ptree;
ptree pt;
boost::property_tree::ptree nodeObject;
nodeObject.put("object.<xmlattr>.id", 12345678);

boost::property_tree::ptree nodeInfo;    
nodeInfo.put("Owner", "Mr. Heik");
nodeInfo.put("Health", "37/100");

// Put everything together
nodeObject.put_child("AdditionalInfo", nodeInfo);
pt.add_child("tree.objects", nodeObject);
write_xml("output.xml", pt);

我尝试使用 put/add/add_child/etc 来获得所需的结果。但没有成功。我必须使用哪些 boost 功能？

Answer 1

这一行:

nodeObject.put("object.<xmlattr>.id", 12345678);

正在向具有给定属性的当前节点的子路径“对象”添加新的子节点。

只需在节点上设置属性即可:

nodeObject.put("<xmlattr>.id", 12345678);

并将节点直接添加到树中的正确路径:

pt.add_child("tree.objects.object", nodeObject);

最终代码:

ptree pt;
boost::property_tree::ptree nodeObject;
nodeObject.put("<xmlattr>.id", 12345678);

boost::property_tree::ptree nodeInfo;
nodeInfo.put("Owner", "Mr. Heik");
nodeInfo.put("Health", "37/100");

nodeObject.put_child("AdditionalInfo", nodeInfo);
pt.add_child("tree.objects.object", nodeObject);
write_xml("output.xml", pt);

输出:

<?xml version="1.0" encoding="utf-8"?>
<tree>
  <objects>
    <object id="12345678">
       <AdditionalInfo>
          <Owner>Mr. Heik</Owner>
          <Health>37/100</Health>
       </AdditionalInfo>
    </object>
  </objects>
</tree>