数字累加

数字累加

setTimeout()定时器

setTimeout(要执行的代码, 等待的毫秒数)
setTimeout(JavaScript 函数, 等待的毫秒数)
例：
setTimeout("alert('对不起, 要你久候')", 3000 )

代码：

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
				<p>1</p>
	</body>
	<script type="text/javascript">
		function addNum(numTop, num,el) {
			console.log(typeof(el));
			if (num != numTop) {
				num = Number(num) + 1;
				document.querySelector(el).innerText= num;
				setTimeout("addNum(" + numTop + ","+num+","+'"'+el+'"'+")", 30); //字符串中传入参数需要拼接
			}
		}
		
		var a = document.querySelector("p").innerText; //1.获取p标签内容，赋值变量a
		addNum(30, a,"p");//2.调用
		
	</script>
</html>
posted @ 2021-11-04 21:57  禾耳  阅读(67)  评论(0)    收藏  举报