一、CSS兼容代码
.transparent {
filter:alpha(opacity=50); /* IE */
-moz-opacity:0.5; /* FireFox old version*/
-khtml-opacity: 0.5; /* Sarfari old version */
opacity: 0.5; /* FireFox */
}
二、Javascript兼容代码
if (!window.jasen.core.Util) {
window.jasen.core.Util = {};
}
var $ = function (id) {
return document.getElementById(id);
}
function style(element, key, value) {
if (typeof element == "string") {
element = $(element);
}
if (value) {
element.style[key] = value;
}
else {
return element.style[key];
}
};
function opacity(element, /*0-100*/opacityValue) {
var opacityValue = parseInt(opacityValue);
style(element, "filter", "alpha(opacity=" + opacityValue + ")");
opacityValue /= 100.0;
style(element, "MozOpacity", opacityValue);
style(element, "KhtmlOpacity", opacityValue);
style(element, "opacity", opacityValue);
};
var Util = window.Util = window.jasen.core.Util;
Util.opacity = opacity;
Util.style = style;
三、范例
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<style type="text/css">
#content
{
width:300px;
margin:20px auto;
}
</style>
<script src="Scripts/jasen.Core.Util.js" type="text/javascript"></script>
<script type="text/javascript">
window.onload = function () {
var seletor = document.getElementById("opacitySeletor");
seletor.options.add(new Option("--请选择--", "100")); for (var i = 0; i <= 100; i++) {
seletor.options.add(new Option(i, i));
} seletor.onmousewheel = function (event) {
event = event || window.event;
var currentIndex = seletor.selectedIndex - event.wheelDelta / 120; if (currentIndex < 0) {
seletor.selectedIndex = seletor.options.length - 1;
}
else if (currentIndex > seletor.options.length - 1) {
seletor.selectedIndex = 0;
}
else {
seletor.selectedIndex = currentIndex;
} seletor.onchange();
return false;
}
} function changeOpacity() {
var element = document.getElementById("opacitySeletor"); if (element.selectedIndex < 0) {
return;
} var opacityValue = element[element.selectedIndex].value; if (opacityValue != "") {
Util.opacity("opacityImg", opacityValue);
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<div id="content">
<select id="opacitySeletor" onchange="return changeOpacity();"></select>
<img id = "opacityImg" src="Images/car.jpg" title="car opacity" alt="car opacity" />
</div>
</div>
</form>
</body>
</html>