<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<p id="p1">啊啊啊啊啊啊啊啊啊啊啊啊啊</p>
</body>
<script>
var p1 = document.getElementById("p1");
var p2 = p1.innerText.split(‘‘);
p1.innerText=‘‘;
var i=0;
var qqq = setInterval(function () {
if (i<p2.length){
p1.innerText +=p2[i];
i++;
}else {
clearInterval(qqq);
}
},100);
</script>
</html>
原文：http://www.cnblogs.com/huahuahua/p/6923331.html