js中的运动
缓慢隐藏与出现
效果：
鼠标移至分享上黄色区域自动向左隐藏。
<!DOCTYPE html>
<html>
<head>
<title></title>
<style type="text/css">
div{
background-color: yellow;
height: 200px;
width: 150px;
position: absolute;
top:50px;
left: -150px;
}
span{
background-color: red;
position: absolute;
top:80px;
left: 150px;
}
</style>
<script type="text/javascript">
window.onload = function(){
var oDiv = document.getElementsByTagName('div')[0];
oDiv.onmouseout = function(){
startMove(-150);
}
oDiv.onmouseover = function(){
startMove(0);
}
}
var timer = null;
function startMove(target){
var oDiv = document.getElementsByTagName('div')[0];
var speed = 10;
if(oDiv.offsetLeft>target)
speed = -10;
//防止定时器被多次调用
clearInterval(timer);
timer = setInterval(function(){
if(oDiv.offsetLeft != target){
oDiv.style.left = oDiv.offsetLeft+speed+'px';
}
else
clearInterval(timer);
}, 30);
}
</script>
</head>
<body>
<div><span>分享</span></div>
</body>
</html>
使用绝对定位，通过获取offsetLeft(相对于浏览器左边框的距离)的值和left来确定黄色区域的位置
图像透明度渐变效果
当鼠标移入图像时颜色变亮，移除时颜色变暗
<!DOCTYPE html>
<html>
<head>
<title></title>
<style type="text/css">
div{
background-color: yellow;
height: 200px;
width: 150px;
filter:alpha(opacity:30);
opacity: 0.3;
}
</style>
<script type="text/javascript">
window.onload = function(){
var oDiv = document.getElementsByTagName('div')[0];
oDiv.onmouseout = function(){
startMove(30);
}
oDiv.onmouseover = function(){
startMove(100);
}
}
var timer = null;
var alpha = 30;
function startMove(target){
var oDiv = document.getElementsByTagName('div')[0];
var speed = 10;
//防止定时器被多次调用
if(alpha > target)
speed = -10;
clearInterval(timer);
timer = setInterval(function(){
if(alpha != target){
alpha += speed;
oDiv.style.filter = "alpha(opacity:"+alpha+")";
oDiv.style.opacity = alpha/100;
}
else
clearInterval(timer);
}, 30);
}
</script>
</head>
<body>
<div></div>
</body>
</html>
