要在最后添加一个元素，请使用JavaScriptpush()方法。JavaScript数组push()方法将给定元素添加到数组的最后，并返回新数组的长度。
您可以尝试运行以下代码以在数组的最后添加元素-
<html>
<head>
<title>JavaScript Array push Method</title>
</head>
<body>
<script>
var numbers = new Array(30, 70, 75, 90);
var length = numbers.push(100);
document.write("new numbers are : " + numbers );
length = numbers.push(200);
document.write("<br />new numbers are : " + numbers );
</script>
</body>
</html>输出结果
new numbers are : 30,70,75,90,100 new numbers are : 30,70,75,90,100,200