مثال خواندن پراپرتی‌های json به صورت پویا و بدون داشتن کلید با nlohmann::json
کد

#include <iomanip>
#include <iostream>
#include <nlohmann/json.hpp>

using json = nlohmann::json;

int main()
{
  // a JSON text
  char text[] = R"(
  {
    "Image": {
      "Width":  800,
      "Height": 600,
      "Title":  "View from 15th Floor",
      "Thumbnail": {
        "Url":    "http://www.example.com/image/481989943",
        "Height": 125,
        "Width":  100
      },
      "Animated" : false,
      "IDs": [116, 943, 234, 38793]
    }
  }
  )";

  // parse and serialize JSON
  json j_complete = json::parse(text);
  std::cout << std::setw(4) << j_complete << std::endl;

  std::cout << "________________________" << std::endl;
  for (const auto &prop : j_complete["Image"].items())
  {
    std::cout << "key: " << prop.key() << std::endl;
    std::cout << "value: " << prop.value() << std::endl;
    std::cout << "" << std::endl;
  }
  return 0;
}

خروجی

{
    "Image": {
        "Animated": false,
        "Height": 600,
        "IDs": [
            116,
            943,
            234,
            38793
        ],
        "Thumbnail": {
            "Height": 125,
            "Url": "http://www.example.com/image/481989943",
            "Width": 100
        },
        "Title": "View from 15th Floor",
        "Width": 800
    }
}
________________________
key: Animated
value: false

key: Height
value: 600

key: IDs
value: [116,943,234,38793]

key: Thumbnail
value: {"Height":125,"Url":"http://www.example.com/image/481989943","Width":100}

key: Title
value: "View from 15th Floor"

key: Width
value: 800

لینک کانال تلگرام : https://t.me/moderncpp_ir
#json #dynamic #read #parse #nlohmann