<html><body><h2>JavaScript 数组方法</h2><p>删除元素会在数组中留下未定义的空洞。</p><p id="demo1"></p><p id="demo2"></p><script>var fruits = ["香蕉","橙子","苹果","芒果"];document.getElementById("demo1").innerHTML ="第一个水果是：" + fruits[0];delete fruits[0];document.getElementById("demo2").innerHTML ="第一个水果是：" + fruits[0];</script></body></html>