JavaScript 对象字面量增强

✏️ Editable

Loading...

Live Preview

⌘+Enter Run⌘+R Reset

Current StepStep 1/3

Unlocked Steps1/3

Next Suggestion

Complete current Step 1 first

1) Current Task & Steps

Current task: Step 1 - 第一步：属性简写
实现 buildUser(name, level)，返回 { name, level }

Write your code in `script.js` for the current Step.
Click "Run Validation" to check if rules pass.
Once current Step passes, the next step unlocks automatically.
You need to pass Step 1 first to unlock Step 2.

Step Deliverables (Check these)

Define function: buildUser(name, level)
Self-check: buildUser("Amy", 2) => {"name":"Amy","level":2}

2) Beginner Explanation (Current Step)

Step task: 实现 buildUser(name, level)，返回 { name, level }
Define function(s): buildUser, then verify results with test inputs.
This step has a specific expected result. Focus on making the function return the correct value.
A function is a reusable block of code. Define it first, then call it.
`return` sends a result back. Without return, you usually can't get the function's result.

3) Starter Template (Type along)

function buildUser(name, level) {
  return null;
}
// Self-check: buildUser("Amy", 2) should return {"name":"Amy","level":2}
console.log(buildUser("Amy", 2));

4) Rule Validation & Hints

📋 当前任务 - Step 1

定义 buildUser
buildUser 返回正确

🔐 学习提示

📖 快速参考

动态 key 必须写成 [key]，写成 key 会得到固定字段名 "key"。

About This Exercise

对象是前端最常见的数据结构之一。

ES6 让对象写法更短、更清楚，特别适合新手减少重复代码和拼写错误。

本关只练三个高频写法：属性简写、方法/字段简写、动态属性名。

Beginner⏱ 15-20 min

Learning Objectives

掌握属性简写（变量名即属性名）
掌握对象内部字段组合写法
掌握计算属性名 [key] 动态生成字段

Scenario

你在做课程配置模块，需要快速组装对象，还要支持动态字段名。这正是对象字面量增强最常见的使用场景。

Why Do This

Frontend JS is not just about knowing the syntax — the key is reliably manipulating the DOM and managing interaction state.
Break down the event flow (trigger -> handle -> update UI) before coding, and you will make significantly fewer errors.
Rule-based validation helps you develop a testable frontend mindset.

Hands-on Practice

Write out the event flow in comments first, then implement the functions.
Add an edge case branch for invalid input or empty data.
Explain why each validation rule is needed.

Common Mistakes

Only testing the happy path without verifying edge inputs or repeated clicks.
Mixing event binding and state updates together, making future maintenance difficult.
Console output looks correct but the UI is not actually updated.

Deliverable

A reusable interaction component scaffold (event flow description + key functions + edge case handling).

My Progress

Completed Steps0 / 3

Total Attempts0

Best Score0%

Completion Criteria (Checkable)

Confirm before completing this Lab

All rules for the current step passCan explain each line of your codeCan name a real-world business scenario for this

Reflection Questions (Recommended)

Describe the event flow of this Lab in 2-3 sentences (trigger -> handle -> update).

What edge case did you add? Why is it easy to miss?

How confident are you with this interaction pattern now?

Not confident yet, need more practiceCan complete similar tasks independentlyCan teach others how to do it