从Ionic 2中的Json字符串中提取值

let jsonString = '{"name": "John", "age": 30, "city": "New York"}';
let jsonObject = JSON.parse(jsonString);

let name = jsonObject.name;
console.log(name); // 输出：John

let jsonString = '{"name": "John", "age": 30, "address": {"city": "New York", "country": "USA"}}';
let jsonObject = JSON.parse(jsonString);

let city = jsonObject.address.city;
let country = jsonObject.address.country;
console.log(city); // 输出：New York
console.log(country); // 输出：USA

let jsonString = '{"fruits": ["apple", "banana", "orange"]}';
let jsonObject = JSON.parse(jsonString);

let firstFruit = jsonObject.fruits[0];
let secondFruit = jsonObject.fruits[1];
console.log(firstFruit); // 输出：apple
console.log(secondFruit); // 输出：banana