Q. I want to use the move function in JS to move the diagonal line down of the small picture, but the code is almost the same. The left can be moved, but the top cannot be moved.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>台球桌</title>
<style type="text/css">
*{
padding:0;
margin:0;
}
p{
background:url(../PICTURE/table.JPG) no-repeat;
height:260px;
width:465px;
}
#ball{}
</style>
<script>
function init(){
var timer = setInterval("move()",50);
}
function move(){
var ball = document.getElementById("ball");
left = parseInt(ball.style.left);
left += 1;
top = parseInt(ball.style.top);
top += 1;
ball.style.left = left + "px";
ball.style.top = top + "px";
}
</script>
</head>
<body onload="init()">
<p>
<img src="../PICTURE/ball.png" id="ball" style="position:absolute;left:6px;top:5px;"/>
</p>
</body>
</html>
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希望您严格按照W3C标准来写JS代码。