c++ - 如何让 boost json 使用正确的数据类型

Question

当我 put_value 使用 int 时，它被写为字符串。有谁知道如何让它作为 int 打印？

#include <iostream>
#include <boost/property_tree/ptree.hpp>
#include <boost/property_tree/json_parser.hpp>

using boost::property_tree::ptree;
using namespace std;

int main(int argc, char* argv[]) {

    ptree node;
    node.put("string", "text here");
    node.put("int", 1);//outputs as "1" and should be 1
    write_json(cout, node, false);//{"string":"text here","int":"1"}

    return 0;
}

Answer 1

图书馆明确表示不支持它。

Boost Property Library 尚未命名为“Boost Json Library”，因为它不是 JSON 库。相反，它是一个属性树库(恰好使用 JSON 子集用于其目的)。

来自documentation :

The property tree dataset is not typed, and does not support arrays as such. Thus, the following JSON / property tree mapping is used:

• JSON objects are mapped to nodes. Each property is a child node.
• JSON arrays are mapped to nodes. Each element is a child node with an empty name. If a node has both named and unnamed child nodes, it cannot be mapped to a JSON representation.
• JSON values are mapped to nodes containing the value. However, all type information is lost; numbers, as well as the literals "null", "true" and "false" are simply mapped to their string form.
• Property tree nodes containing both child nodes and data cannot be mapped.

和

JSON round-trips, except for the type information loss.