在线运行代码 - 菜鸟教程

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(cainiaoplay.com)</title>
</head>
<body>

<p id="demo">单击按钮显示“苹果”最后一次出现的位置：</p>
<button onclick="myFunction()">点我</button>
<script>
function myFunction(){
	var fruits=["Banana","Orange","Apple","Mango","Banana","Orange","Apple","Mango"];
	var a=fruits.lastIndexOf("Apple")
	var x=document.getElementById("demo");
	x.innerHTML=a;
}
</script>
<p><b>注意:</b>lastIndexOf方法在JavaScript 1.6被引进，在Internet Explorer 8或更早的版本中不支持。</p>

</body>
</html>
源代码

动行结果
