本文目录一览：
雪花飘落的JS代码
N是管雪花的数量，Y是雪花下落的速度，(document.layers)?window.innerHeight:window.document.body.clientHeight;是雪花下落的尺寸，可以改为=(document.layers)?window.innerHeight+100:window.document.body.clientHeight;+100，下落尺寸加大100。
Dreamweaver海报首页怎样做出雪花飘
首页雪花飘的效果是通过图片+JS代码做出来的。
先做flash引导线制作雪花飘落的动画图片。
在这个雪花图片中加入JS代码即可。
以下是参考代码：
script language="JavaScript"
!--
N =20;
Y = new Array();
X = new Array();
S = new Array();
A = new Array();
B = new Array();
M = new Array();
V = (document.layers)?1:0;
iH=(document.layers)?window.innerHeight:window.document.body.clientHeight;
iW=(document.layers)?window.innerWidth:window.document.body.clientWidth;
for (i=0; i N; i++){
Y[i]=Math.round(Math.random()*iH);
X[i]=Math.round(Math.random()*iW);
S[i]=Math.round(Math.random()*5+2);
A[i]=0;
B[i]=Math.random()*0.1+0.1;
M[i]=Math.round(Math.random()*1+7);
}
if (V){
for (i = 0; i N; i++)
{document.write("LAYER NAME='sn"+i+"' LEFT=0 TOP=0 BGCOLOR='#FFFFF0' CLIP='0,0,"+M[i]+","+M[i]+"';z-index: 1font color=white size=3 face='Wingdings'T/font/LAYER")}
}
else{
document.write('div style="position:absolute;top:0px;left:0px;z-index: 1"');
document.write('div style="position:relative;z-index: 1"');
for (i = 0; i N; i++)
{document.write('div id="si" style="position:absolute;z-index: 1;top:0;left:0;width:'+M[i]+';height:'+M[i]+';font-size:'+M[i]+'"font color=white size=3 face="Wingdings"T/font/div')}
document.write('/div/div');
}
function snow(){
var H=(document.layers)?window.innerHeight:window.document.body.clientHeight;
var W=(document.layers)?window.innerWidth:window.document.body.clientWidth;
var T=(document.layers)?window.pageYOffset:document.body.scrollTop;
var L=(document.layers)?window.pageXOffset:document.body.scrollLeft;
for (i=0; i N; i++){
sy=S[i];
sx=S[i]*Math.cos(A[i]);
Y[i]+=sy;
X[i]+=sx;
if (Y[i] H){
Y[i]=-10;
X[i]=Math.round(Math.random()*W);
M[i]=Math.round(Math.random()*1+7);
S[i]=Math.round(Math.random()*5+2);
}
if (V){document.layers['sn'+i].left=X[i];document.layers['sn'+i].top=Y[i]+T}
else{si[i].style.pixelLeft=X[i];si[i].style.pixelTop=Y[i]+T}
A[i]+=B[i];
}
setTimeout('snow()',40);
}
snow()
//--
/script
网页飘雪花的代码是什么
在后台添加js特效可实现这样的效果。
js代码为：
script language="JavaScript"
!--
var no = 5; //雪片数目
var speed = 20; //飘动速度。(值越大越慢)
var ns4up = (document.layers) ? 1 : 0; //当前浏览器类型，如果是NS则为1
var ie4up = (document.all) ? 1 : 0; //当前浏览器类型，如果是IE则为1
var s, x, y, sn, cs;
var a, r, cx, cy;
var i, doc_width = 800, doc_height = 600;
x = new Array();
y = new Array();
r = new Array();
cx = new Array();
cy = new Array();
s = 8; //每次下落的高度，越小越平滑，但是也越慢
if (ns4up) { //以NS兼容方式
doc_width = self.innerWidth; //取页面宽度
doc_height = self.innerHeight; //取页面高度
}
else
if (ie4up) { //以IE兼容方式
doc_width = document.body.clientWidth; //取页面宽度
doc_height = document.body.clientHeight; //取页面高度
}
for (i = 0; i no; ++ i) { //根据前面定义的雪片数目写进相应数目的层
initSnow(); //随机初始化层的坐标
if (ns4up) { //如果浏览器是NS
//用layer作为雪片(星号)的容器
document.write("layer name="dot"+ i +"" left="1" ");
document.write("top="1" visibility="show"font color="red"");
document.write("*/font/layer");
}
else
if (ie4up) { //如果浏览器是IE
//用div作为雪片的容器
document.write("div id="dot"+ i +"" style="POSITION: ");
document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: ");
document.write("visible; TOP: 15px; LEFT: 15px;"font color="red"");
document.write("*/font/div");
}
}
//初始化雪片，生成随机坐标
function initSnow() {
a = 6;
r[i] = 1;
sn = Math.sin(a);
cs = Math.cos(a);
cx[i] = Math.random() * doc_width + 1;
cy[i] = Math.random() * doc_height + 1;
x[i] = r[i] * sn + cx[i];
y[i] = cy[i];
}
//计算雪花位置，从新位置上出现，看起来就像是新产生的一样。
function makeSnow() {
r[i] = 1;
cx[i] = Math.random() * doc_width + 1;
cy[i] = 1;
x[i] = r[i] * sn + cx[i];
y[i] = r[i] * cs + cy[i];
}
//雪花下落的计算
function updateSnow() {
r[i] += s;
x[i] = r[i] * sn + cx[i];
y[i] = r[i] * cs + cy[i];
}
//在NS浏览器上处理雪片下落的主程序
function SnowdropNS() {
for (i = 0; i no; ++ i) { //依次处理每片雪花
updateSnow(); //下落
if ((x[i] = 1) || (x[i] = (doc_width - 20)) || (y[i] = (doc_height - 20))) { //如果超出屏幕范围
makeSnow(); //则调整雪片到新位置上
doc_width = self.innerWidth; //更新页面宽度数据
doc_height = self.innerHeight; //更新页面高度数据
}
document.layers["dot"+i].top = y[i]; //改变层的Y坐标，应用新的位置
document.layers["dot"+i].left = x[i]; //改变层的X坐标，应用新的位置
}
setTimeout("SnowdropNS()", speed);
}
//在IE浏览器上处理雪片下落的主程序
function SnowdropIE() {
for (i = 0; i no; ++ i) { //依次处理每片雪花
updateSnow(); //下落
if ((x[i] = 1) || (x[i] = (doc_width - 20)) || (y[i] = (doc_height - 20))) { //如果超出屏幕范围
makeSnow(); //则调整雪片到新位置上
doc_width = document.body.clientWidth; //更新页面宽度数据
doc_height = document.body.clientHeight; //更新页面高度数据
}
document.all["dot"+i].style.pixelTop = y[i]; //改变层的坐标，应用新的位置
document.all["dot"+i].style.pixelLeft = x[i];
}
setTimeout("SnowdropIE()", speed); //准备下一次下落过程。
}
if (ns4up) { //如果是NS
SnowdropNS(); //调用SnowdropNS使雪片下落
}
else
if (ie4up) { //如果是NS
SnowdropIE(); //调用SnowdropIE使雪片下落
}
--
/script
说明：可以根据自己的需求根据说明进行相应参数的修改
求网页飘雪花源代码
把下列代码加到网页的Body/Body标签之间
html
head
title:::飘雪花效果:::网页特效代码:::失落网家园;/title
/head
BODY bgcolor="#000000"
SCRIPT language=JavaScript1.2
var snowsrc="img/snow.gif"
var no = 10;
var ns4up = (document.layers) ? 1 : 0; // browser sniffer
var ie4up = (document.all) ? 1 : 0;
var dx, xp, yp; // coordinate and position variables
var am, stx, sty; // amplitude and step variables
var i, doc_width = 800, doc_height =600;
if (ns4up) {
doc_width = self.innerWidth;
doc_height = self.innerHeight;
} else if (ie4up) {
doc_width = document.body.clientWidth;
doc_height = document.body.clientHeight;
}
dx = new Array();
xp = new Array();
yp = new Array();
am = new Array();
stx = new Array();
sty = new Array();
for (i = 0; i no; ++ i) {
dx[i] = 0; // set coordinate variables
xp[i] = Math.random()*(doc_width-50); // set position variables
yp[i] = Math.random()*doc_height;
am[i] = Math.random()*20; // set amplitude variables
stx[i] = 0.02 + Math.random()/10; // set step variables
sty[i] = 0.7 + Math.random(); // set step variables
if (ns4up) { // set layers
if (i == 0) {
document.write("layer name="dot"+ i +"" left="15" top="15" visibility="show"a href=""img src='"+snowsrc+"' border="0"/a/layer");
} else {
document.write("layer name="dot"+ i +"" left="15" top="15" visibility="show"img src='"+snowsrc+"' border="0"/layer");
}
} else if (ie4up) {
if (i == 0) {
document.write("div id="dot"+ i +"" style="POSITION: absolute; Z-INDEX: "+ i +"; VISIBILITY: visible; TOP: 15px; LEFT: 15px;"a href=""img src='"+snowsrc+"' border="0"/a/div");
} else {
document.write("div id="dot"+ i +"" style="POSITION: absolute; Z-INDEX: "+ i +"; VISIBILITY: visible; TOP: 15px; LEFT: 15px;"img src='"+snowsrc+"' border="0"/div");
}
}
}
function snowNS() { // Netscape main animation function
for (i = 0; i no; ++ i) { // iterate for every dot
yp[i] += sty[i];
if (yp[i] doc_height-50) {
xp[i] = Math.random()*(doc_width-am[i]-30);
yp[i] = 0;
stx[i] = 0.02 + Math.random()/10;
sty[i] = 0.7 + Math.random();
doc_width = self.innerWidth;
doc_height = self.innerHeight;
}
dx[i] += stx[i];
document.layers["dot"+i].top = yp[i];
document.layers["dot"+i].left = xp[i] + am[i]*Math.sin(dx[i]);
}
setTimeout("snowNS()", 10);
}
function snowIE() { // IE main animation function
for (i = 0; i no; ++ i) { // iterate for every dot
yp[i] += sty[i];
if (yp[i] doc_height-50) {
xp[i] = Math.random()*(doc_width-am[i]-30);
yp[i] = 0;
stx[i] = 0.02 + Math.random()/10;
sty[i] = 0.7 + Math.random();
doc_width = document.body.clientWidth;
doc_height = document.body.clientHeight;
}
dx[i] += stx[i];
document.all["dot"+i].style.pixelTop = yp[i];
document.all["dot"+i].style.pixelLeft = xp[i] + am[i]*Math.sin(dx[i]);
}
setTimeout("snowIE()", 10);
}
if (ns4up) {
snowNS();
} else if (ie4up) {
snowIE();
}
/SCRIPT
table border="0" width="100%" cellpadding="0"
tr
td width="100%"font color="#ffffff" size="2"b飘雪花效果/b注意保存这个图片（img border="1" src="img/snow.gif" width="16" height="17"）/font/td
/tr
tr
td width="100%"
/table
script language="JavaScript" type="text/javascript" src="js.js"/scripttr/body
/html