Javascript 遮罩层和加载效果代码

 //loading
function showLoad(tipInfo) {
var iWidth = 120; //弹出窗口的宽度;
var iHeight = 0; //弹出窗口的高度;
var scrolltop = 0;
var scrollleft = 0;
var cheight = 0;
var cwidth = 0;
var eTip = document.createElement('div');
eTip.setAttribute('id', 'tipDiv');
eTip.style.position = 'absolute';
eTip.style.display = 'none';
eTip.style.border = 'solid 0px #D1D1D1';
eTip.style.backgroundColor = '#4B981D';
eTip.style.padding = '5px 15px';
if(document.body.scrollTop){//这是一个js的兼容
scrollleft=document.body.scrollLeft;
scrolltop=document.body.scrollTop;
cheight=document.body.clientHeight;
cwidth=document.body.clientWidth;
}
else{
scrollleft=document.documentElement.scrollLeft;
scrolltop=document.documentElement.scrollTop;
cheight=document.documentElement.clientHeight;
cwidth=document.documentElement.clientWidth;
}
iHeight = eTip.offsetHeight;
var v_left=(cwidth-iWidth)/2 + scrollleft; //
var v_top=(cheight-iHeight)/2+ scrolltop;
eTip.style.left = v_left + 'px';
eTip.style.top = v_top + 'px';
eTip.innerHTML = '<img src='Images/loading.gif' style='float:left;' />　<span style='color:#ffffff; font-size:12px'>' + tipInfo + '</span>';
try {
document.body.appendChild(eTip);
} catch (e) { }
$("#tipDiv").css("float", "right");
$("#tipDiv").css("z-index", "99");
$('#tipDiv').show();
ShowMark();
}
function closeLoad() {
$('#tipDiv').hide();
HideMark();
}
//显示蒙灰层
function ShowMark() {
var xp_mark = document.getElementById("xp_mark");
if (xp_mark != null) {
//设置DIV
xp_mark.style.left = 0 + "px";
xp_mark.style.top = 0 + "px";
xp_mark.style.position = "absolute";
xp_mark.style.backgroundColor = "#000";
xp_mark.style.zIndex = "1";
if (document.all) {
xp_mark.style.filter = "alpha(opacity=50)";
var Ie_ver = navigator["appVersion"].substr(22, 1);
if (Ie_ver == 6 || Ie_ver == 5) { hideSelectBoxes(); }
}
else { xp_mark.style.opacity = "0.5"; }
xp_mark.style.width = "100%";
xp_mark.style.height = "100%";
xp_mark.style.display = "block";
}
else {
//页面添加div explainDiv,注意必须是紧跟body 内的第一个元素.否则IE6不正常.
$("body").prepend("<div id='xp_mark' style='display:none;'></div>");
ShowMark(); //继续回调自己
}
}
//隐藏蒙灰层
function HideMark() {
var xp_mark = document.getElementById("xp_mark");
xp_mark.style.display = "none";
var Ie_ver = navigator["appVersion"].substr(22, 1);
if (Ie_ver == 6 || Ie_ver == 5) { showSelectBoxes(); }
}