<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>下雪效果</title>
<script type="text/javascript" language="javascript">
(function(){
function k(a,b,c){
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a.addEventListener(b,c,false);
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window.onload=function(){
b();
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function h(){
var a={};
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function l(){
var a=document.body,b;
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function i(a){
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this.createEl(this.parent,a);
this.size=Math.random()*5+5;
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this.el.style.height=Math.round(this.size)+"px";
this.maxLeft=document.body.offsetWidth-this.size;
this.maxTop=document.body.offsetHeight- this.size;
this.left=Math.random()*this.maxLeft;
this.top=h().top+1;this.angle=1.4+0.2*Math.random();
this.minAngle=1.4;this.maxAngle=1.6;
this.angleDelta=0.01*Math.random();
this.speed=2+Math.random()
}
var j=false;
g(function(){j=true});
var f=true;window.createSnow=function(a,b){
if(j){
var c=[];
m=setInterval(function(){
f&&b>c.length&&Math.random()<b*0.0025&&c.push(new i(a));
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c[d]=null;
c.splice(d,1);
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c[d].draw();
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},40);
k(window,"scroll",function(){
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g(function(){
createSnow(a,b);
})
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};
window.removeSnow=function(){
f=false;
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i.prototype={createEl:function(a,b){
this.el=document.createElement("img");
this.el.setAttribute("src",b+"http://mimg.127.net/hxm/quan/hd/111207_sdj/style/img/snow.gif");
this.el.style.position="absolute";
this.el.style.display="block";
this.el.style.zIndex="99999";
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move:function(){
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createSnow("", 80);
</script>
</head>
<body style="background-color:#77aac2">
</body>
</html>
相关资料：https://jucelin.com/snow-js.html
原文：https://www.cnblogs.com/time20181212/p/js20181212.html