<!DOCTYPE html>
<html> <head>
<meta charset="UTF-8">
<title>只传一个参数</title>
<style type="text/css">
.div {
width: 100px;
height: 100px;
background-color: chartreuse;
margin-top: 50px;
position: absolute;
left: -100px;
top: 0;
cursor: pointer;
}
.div span{
display: block;
width: 20px;
height: 50px;
position: absolute;
right: -20px;
top: 50%;
margin-top: -25px;
background-color: coral;
font-size: 10px;
padding: 5px;
-webkit-box-sizing: border-box;
box-sizing: border-box;
}
</style>
<script type="text/javascript">
window.onload = function(){
var oDiv = document.getElementById('div');
oDiv.onmouseover = function(){
start(0);
};
oDiv.onmouseout = function(){
start(-100);
};
};
var timer = null;
//功能一抹一样的函数，参数越少越好。
function start(iTarget) {
var oDiv = document.getElementById('div');
clearInterval(timer);
timer = setInterval(function() {
var speed = 0;
if(oDiv.offsetLeft>iTarget){
speed = -10;
}else{
speed = 10;
};
if(oDiv.offsetLeft == iTarget) {
clearInterval(timer);
}
else{
oDiv.style.left = oDiv.offsetLeft + speed + 'px';
} }, 30)
};
</script>
</head> <body>
<div class="div" id="div"><span>分享到</span></div>
</body> </html>
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