那个大神帮我看看这段JS IE报错
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>Insert title here</title>
<style>
.mesWindow {
border: #666 1px solid;
background: #fff;
}
.mesWindowTop {
border-bottom: #eee 1px solid;
margin-left: 4px;
padding: 3px;
font-weight: bold;
text-align: left;
font-size: 12px;
}
.mesWindowContent {
margin: 4px;
font-size: 12px;
}
.mesWindow .close {
height: 15px;
width: 28px;
border: none;
cursor: pointer;
text-decoration: underline;
background: #fff
}
</style>
<script language="javascript" type="text/javascript">
var isIe = (document.all) ? true : false;
//设置select的可见状态
function setSelectState(state) {
var
objl = document.getElementsByTagName
('select');
for (var i = 0; i < objl.length; i++) {
objl[i].style.visibility = state;
}
}
//弹出方法
function showMessageBox(wTitle, content, pos, wWidth) {
closeWindow();
var bWidth = parseInt(document.documentElement.scrollWidth);
var bHeight = parseInt(document.documentElement.scrollHeight);
if (isIe) {
setSelectState('hidden');
}
var back = document.createElement("div");
back.id = "back";
var styleStr = "top:0px;left:0px;position:absolute;background:#666;width:" + bWidth + "px;height:" + bHeight + "px;";
styleStr += (isIe) ? "filter:alpha(opacity=0);" : "opacity:0;";
back.style.cssText = styleStr;
document.body.appendChild(back);
showBackground(back, 50);
}
//让背景渐渐变暗
function showBackground(obj, endInt) {
if (isIe) {
obj.filters.alpha.opacity += 1;
//var opacity = parseInt(obj.style.filter.replace("alpha(opacity = ", "").replace(")", "")) + 1;
//obj.style.filter = "alpha(opacity = " + (opacity) + ")";
if (obj.filters.alpha.opacity < endInt) {
setTimeout(function () { showBackground(obj, endInt) }, 5);
}
} else {
var al = parseFloat(obj.style.opacity); al += 0.01;
obj.style.opacity = al;
if (al < (endInt / 100))
{ setTimeout(function () { showBackground(obj, endInt) }, 5); }
}
}
//关闭窗口
function closeWindow() {
if (document.getElementById('back') != null) {
document.getElementById('back').parentNode.removeChild(document.getElementById('back'));
}
if (document.getElementById('mesWindow') != null) {
document.getElementById('mesWindow').parentNode.removeChild(document.getElementById('mesWindow'));
}
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