
先上效果图:

源码:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<p id="showStr"></p>
<p style="display:none" id="string">
逐字出来的效果,哈哈哈哈哈哈哈哈哈
</p>
<script type="text/javascript">
var index = 0;
var str = document.getElementById("string").innerHTML;
setInterval(function() {
if(index == str.length) {
//清除定时器
clearInterval();
//若要让效果无限循环,把index归0即可
// index = 0;
}
var a = document.getElementById("showStr")
a.innerText = str.substring(0, index++);
},400)
</script>
</body>
</html>