HTML5 JSON多维数组键与javascript或jQuery

从未知大小的对象中获取所有键的关键是递归。这里我有两个解决方案；一个是功能性的，一个是面向对象的。除了你的数据，我还创建了一些其他数据来测试。

以下是带有完整代码的回购：https://github.com/vasilionjea/json-keys

数据：

var data = {
  continents: {
    europe: {
      countries: [
        {
          'country-name': 'italy',
          cities: [
            { 'city-name': 'Rome', title: 'Roma Dolor', population:873, gdb: 301 },
            { 'city-name': 'Venice', title: 'Venice Veggies.', population:456, gdb: 244 }
          ]
        },
        {
          'country-name': 'france',
          cities: [
            { 'city-name': 'Paris', title: 'De Ipsum', population:7123, gdb: 77 },
            { 'city-name': 'Marseille', title: 'La Mipsum', population:73, gdb: 7 }
          ]
        }
      ]
    },
    'north-america': {
      countries: [
        {
          'country-name': 'canada',
          cities: [
            { 'city-name': 'Montreal', title: 'The city of lorem ipsum!', population:99, gdb: 011 },
            { 'city-name': 'Quebec', title: 'Veggie Ipsum.', population:123, gdb: 101 }
          ]
        },
        {
          'country-name': 'usa',
          cities: [
            { 'city-name': 'New York', title: 'Empire State', population:1001001, gdb: 1010 },
            { 'city-name': 'San Francisco', title: 'SF Bridge', population:20123, gdb: 202 }
          ]
        }
      ]
    }
  }
}

功能方式：

/*
 * Functional example.
 * Retrieves all keys from an object of unknown size using recursion.
 */
function _isObject(obj) {
  return Object.prototype.toString.call(obj) === "[object Object]";
}
function _eachKey(obj, callback) {
  Object.keys(obj).forEach(callback);
}
var _container = [];
function collectKeys(data) {
  _eachKey(data, function(key) {
    _container.push(key);
    if (_isObject(data[key])) {
      collectKeys(data[key]);
    }
    if (Array.isArray(data[key])) {
      // Because we're looping through an array and each array's item is an object, 
      // the `collectKeys` function is receiving each object of the array as an argument.
      data[key].forEach(collectKeys);
    }
  });
  return _container;
}
// Execute the function
var myKeys = collectKeys(data);

面向对象的方式：

/*
 * Object Oriented example.
 * Retrieves all keys from an object of unknown size using recursion.
 */
function JSONKeys(obj) {
  this._container = [];
  if (this._isObject(obj)) {
    // Just a normal object literal.
    this._data = obj;
  } else if (typeof obj === 'string') {
    // Just in case the data was passed in as a valid JSON string.
    this._data = JSON.parse(obj);
  } else {
    throw new Error('The provided argument must be an object literal or a JSON string.');
  }
}
JSONKeys.prototype = {
  constructor: JSONKeys,
  _isObject: function(obj) {
    return Object.prototype.toString.call(obj) === "[object Object]";
  },
  _eachKey: function(obj, callback) {
   // Using `bind(this)` makes sure that the `this` value in the `_collect` method 
   // isn't set to the global object (window).
    Object.keys(obj).forEach(callback.bind(this));
  },
  _recur: function(key, data) {
      // If this key's value is also an object go deeper.
      if (this._isObject(data[key])) {
        this._collect(data[key]);
      }
      if (Array.isArray(data[key])) {
        // * Because we're looping through an array and each array's item is an object, 
        //   the `_collect` method is receiving each object of the array as an argument.
        // * Using `bind(this)` makes sure that the `this` value in the `_collect` method 
        //   isn't set to the global object (window).
        data[key].forEach(this._collect.bind(this));
      }
  },
  _collect: function(data) {
    this._eachKey(data, function(key) {
      this._container.push(key);
      // Continue collecting
      this._recur(key, data);
    });
  },
  getAll: function() {
    this._collect(this._data);
    return this._container;
  }
};
// Create a new instance passing the data.
var keysObject = new JSONKeys(data);
allKeys = keysObject.getAll();