某需求需要这么玩
于是写了个，备份用
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<script src="https://cdn.staticfile.org/jquery/3.2.1/jquery.min.js"></script>
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
body {
margin: 0px;
padding: 0px;
}
.container {
position: relative;
background-color:pink;
height:500px;
width:100%;
overflow: hidden;
}
.danmaku {
display: inline-block;
position: absolute;
overflow: hidden;
}
</style>
</head>
<body>
<div class="container">
</div>
<div id="adddanmaku">click me!</div>
<script>
(document).ready(function(){("#adddanmaku").click(function(){
addDanmaku("danmakutest!");
});
});
function addDanmaku(str)
{
(".container").append("<div class=\"danmaku\">" + str + "</div>");
var _dm =(".container").children(".danmaku").last();
var _width = _dm.width();
var container_height = (".container").height();
var randtop = Math.floor(Math.random()*3*100);//5根据container高度进行自行调整
var _top = randtop>container_height?"0":randtop;
_dm.css({"right": -(_width),
"top": _top,
"color": "#"+(~~(Math.random()*(1<<24))).toString(16)//随机颜色
});
_dm.animate({left:-(_width)}, 16000, "linear", function(){(this).remove();});//弹幕滑行时间可自行调整or随机
}
</script>
</body>
</html>
以上，代码在线：https://codepen.io/anon/pen/gXEEaB
那个随机颜色是某天看到知乎的一篇回答顺手记下的。
地址是： https://www.zhihu.com/question/48187821/answer/110002647