JavaScript-图片库

第四章：JavaScript 图片交互

<ul>
    <li><a href="images/3840x2160-3122452-creative-wallpapers.jpg" onclick="showpic(this);return false;">1</a></li>
    <li><a href="images/3840x2160-3374593-free-dusk-wallpapers.jpg" onclick="showpic(this);return false;">2</a></li>
    <li><a href="images/3840x2160-3957507-photos-wallpapers.jpg">3</a></li>
    <li><a href="images/3840x2160-4279191-stunning-retina-wallpapers.jpg">4</a></li>
  </ul>

//占位符
  <img src="images/3840x2160-3122452-creative-wallpapers.jpg" alt="" id="placeholder">