json_parser.dart

import 'dart:convert';

dynamic parseJson(String jsonString, String path) {
  var json = jsonDecode(jsonString);

  List<String> parts = path.split('.');
  dynamic element = json;

  for (var part in parts) {
    if (part.contains('[') && part.contains(']')) {
      var indexStart = part.indexOf('[');
      var indexEnd = part.indexOf(']');

      String key = part.substring(0, indexStart);
      int index = int.parse(part.substring(indexStart + 1, indexEnd));

      element = element[key][index];
    } else {
      element = element[part];
    }
  }

  return element;
}