代码示例:(标识:eg_js_array_length)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 数组</h1>

<p>length 属性返回数组长度。</p>

<p id="demo"></p>

<script>
var fruits = ["Banana", "Orange", "Apple", "Mango"];
document.getElementById("demo").innerHTML = fruits.length;
</script>

</body>
</html>
运行结果: