c++ - Boost JSON解析器和IP地址

Question

我想获取具有 IP 地址的节点的子节点。以下是我正在使用的引用 JSON 格式和代码。

{  
"nodes":{  
  "192.168.1.1": {  
     "type":"type1",         
     "info":"info1",
     "error":"error1"
  },
  "192.168.1.2":{  
     "type":"type2",         
     "info":"info2",
     "error":"error2"
  },
  "test":{  
     "type":"type2",         
     "info":"info2",
     "error":"error2"
  }
 }
}

下面是读取上述json数据的引用代码。

using boost::property_tree::ptree;
ptree pt;
std::string ttr("test.json");
read_json(ttr, pt);

BOOST_FOREACH(ptree::value_type &v, pt.get_child("nodes"))
{
    std::string key_ = v.first.data();
    std::string val_ = v.second.data();        

    boost::optional< ptree& > child = pt.get_child_optional( "nodes.192.168.1.1" );
    if( !child )
    {
        std::cout << "Child Node Missing.............." << std::endl; //Always shows Node Missing. How to deal with "." as key ?
    }
    else
        std::cout << "Child Node Not Missing.............." << std::endl;        
}

如果节点包含“.”，您能否建议如何读取子节点？ ( IP地址 ) ？这里“nodes.test”可以工作，但“nodes.192.168.1.1”将不起作用，因为它包含“.”。作为字符串？如何让它工作？

提前致谢。

Answer 1

来自docs :

To use a separator character other than default '.', you need to construct a path object explicitly. The path type for a ptree is a string_path instantiation, so the easiest way to refer to it is ptree::path_type. This way you can use trees that have dots in their keys[.]

在你的情况下:

boost::optional< ptree& > child = pt.get_child_optional(ptree::path_type("nodes/192.168.1.1", '/'));