javascript-development-lab/03-loop/index.html at main · coowinit/javascript-development-lab · GitHub

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<!DOCTYPE html>
<html lang="zh-CN">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>03 Loop｜JavaScript Development Lab</title>
  <link rel="stylesheet" href="css/style.css">
</head>
<body>
  <main class="container">
    <header class="hero">
      <p class="eyebrow">JavaScript Development Lab · 03</p>
      <h1>循环与数据遍历</h1>
      <p class="lead">通过一组产品数据，观察 <code>for</code>、<code>while</code> 和 <code>for...of</code> 如何重复执行代码，并把数据逐条输出到页面。</p>
    </header>

    <section class="panel">
      <div class="section-head">
        <div>
          <span class="step">实验 A</span>
          <h2>for 循环</h2>
        </div>
        <code>for (let i = 0; i &lt; products.length; i++)</code>
      </div>
      <div id="for-list" class="product-grid"></div>
    </section>

    <section class="panel">
      <div class="section-head">
        <div>
          <span class="step">实验 B</span>
          <h2>for...of 遍历</h2>
        </div>
        <code>for (const product of products)</code>
      </div>
      <ul id="for-of-list" class="simple-list"></ul>
    </section>

    <section class="panel">
      <div class="section-head">
        <div>
          <span class="step">实验 C</span>
          <h2>while 循环</h2>
        </div>
        <code>while (count &lt; 5)</code>
      </div>
      <div id="while-result" class="number-row"></div>
    </section>

    <section class="panel note">
      <h2>本章观察重点</h2>
      <ol>
        <li>循环为什么需要“开始条件、继续条件、变化条件”。</li>
        <li>数组的 <code>length</code> 为什么经常和循环一起出现。</li>
        <li><code>for</code> 适合需要索引时；<code>for...of</code> 适合直接读取每一项。</li>
        <li><code>while</code> 如果条件一直成立，会形成死循环。</li>
      </ol>
    </section>
  </main>

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