使用lodash或es6编写一个函数，该函数接受具有深度嵌套属性的对象，并返回仅具有选定属性的新对象

const _ = require('lodash');

function pickProperties(obj, properties) {
  return _.pick(obj, properties);
}

const obj = {
  a: 1,
  b: {
    c: 2,
    d: {
      e: 3,
      f: 4
    }
  },
  g: 5
};

const selectedObj = pickProperties(obj, ['a', 'b.d.e', 'g']);
console.log(selectedObj);

function pickProperties(obj, properties) {
  const selectedObj = {};
  
  for (let property of properties) {
    let value = obj;
    for (let key of property.split('.')) {
      if (value && value.hasOwnProperty(key)) {
        value = value[key];
      } else {
        value = undefined;
        break;
      }
    }
    selectedObj[property] = value;
  }
  
  return selectedObj;
}

const obj = {
  a: 1,
  b: {
    c: 2,
    d: {
      e: 3,
      f: 4
    }
  },
  g: 5
};

const selectedObj = pickProperties(obj, ['a', 'b.d.e', 'g']);
console.log(selectedObj);