<!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 content="text/html; http-equiv="Content-Type" charset=utf-8"/>
<title></title>
<script type="text/javascript">
function $(idElemento) {
return document.getElementById(idElemento);
}
var clase = function() {
cantidad = 0;
this.spinButton = function(acc){
cantidad = (acc == undefined) ? cantidad : (acc) ? cantidad+5 : cantidad-5;
if(cantidad < 0) { cantidad = 0; $('cant').value = 0;}
if(cantidad > 50) { cantidad = 50; $('cant').value = 50;}
$('cant').value = cantidad;
}
}
a= new clase();
</script>
<style type="text/css">
div.botonera {
display: inline-block;
}
.incrementable {
vertical-align: middle;
position: relative;
left: -6px;
top: -2px;
}
.botonera button {
display: block;
background: transparent;
border: none;
outline: none;
padding: 0;
margin: 0;
}
.botonera button img{
text-align: left;
vertical-align: middle;
}
</style>
</head>
<body>
<form>
<input type="text" name="cant" id="cant" value="0" readonly="readonly" size="2" />
<div class="botonera incrementable">
<button type="button" value="." onclick="a.spinButton(true)">
<img src="spin_up.png" alt="" border="0" width="16px" height="11px" />
</button>
<button type="button" value="." onclick="a.spinButton(false)">
<img src="spin_down.png" alt="" border="0" width="16px" height="11px" />
</button>
</div>
</form>
</body>
</html>