如何解析来自ajax get请求的对象内部的值？

{
  "user": {
    "id": 1,
    "name": "John Doe",
    "email": "john.doe@example.com"
  },
  "posts": [
    {
      "id": 1,
      "title": "First Post",
      "content": "This is the first post."
    },
    {
      "id": 2,
      "title": "Second Post",
      "content": "This is the second post."
    }
  ]
}

// 假设 xhr 是 XMLHttpRequest 对象，已经处理了请求并得到了响应文本
var responseText = xhr.responseText;

// 解析 JSON 数据
var data = JSON.parse(responseText);

// 访问对象内部的值
var userId = data.user.id;
var userName = data.user.name;
var userEmail = data.user.email;

console.log(userId); // 输出: 1
console.log(userName); // 输出: John Doe
console.log(userEmail); // 输出: john.doe@example.com

// 遍历 posts 数组
data.posts.forEach(function(post) {
  console.log(post.title); // 输出每个帖子的标题
});

fetch('https://api.example.com/data')
  .then(response => response.json()) // 自动解析 JSON 数据
  .then(data => {
    var userId = data.user.id;
    var userName = data.user.name;
    var userEmail = data.user.email;

    console.log(userId); // 输出: 1
    console.log(userName); // 输出: John Doe
    console.log(userEmail); // 输出: john.doe@example.com

    data.posts.forEach(function(post) {
      console.log(post.title); // 输出每个帖子的标题
    });
  })
  .catch(error => console.error('Error:', error));