关于从json中提取变量的问题

// 假设有一个json字符串
var jsonString = '{"name": "John", "age": 30, "city": "New York"}';

// 将json字符串转换为JavaScript对象
var jsonObj = JSON.parse(jsonString);

// 从对象中提取变量
var name = jsonObj.name;
var age = jsonObj.age;
var city = jsonObj.city;

console.log(name); // 输出: John
console.log(age); // 输出: 30
console.log(city); // 输出: New York

var json = {
  "person": {
    "name": "John",
    "age": 30,
    "address": {
      "city": "New York",
      "country": "USA"
    }
  }
};

var name = json.person.name;
var age = json.person.age;
var city = json.person.address.city;
var country = json.person.address.country;

console.log(name); // 输出: John
console.log(age); // 输出: 30
console.log(city); // 输出: New York
console.log(country); // 输出: USA