//为页面添加所需要的元素
var xp_needdiv="";
xp_needdiv="<div id=\"xp_mark\" style=\"display:none;\"></div>";
document.write(xp_needdiv);
//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="#656565";
         xp_mark.style.zIndex="99997"
         if(document.all)
         {
            xp_mark.style.filter="alpha(opacity=30)";
            var Ie_ver=navigator["appVersion"].substr(22,1) 
            if(Ie_ver==6||Ie_ver==5){hideSelectBoxes();}
         }
         else{xp_mark.style.opacity="0.3";}
         xp_mark.style.width="100%";
         var heights=XP_getPageSize().h;
         if(heights<600)
         {
            heights=620;
         }
         xp_mark.style.height=heights+"px";
         xp_mark.style.display="block";
     }
     else{alert("页面上没有ID为'xp_mark'的DIV！");}     
}
//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();}
}
//获取页面的高度与宽度
function XP_getPageSize()
{
    var pt = {w:0,h:0};	
    if (window.innerHeight && window.scrollMaxY) 
    {  
      pt.w = document.body.scrollWidth;
      pt.h = window.innerHeight + window.scrollMaxY;
    }
    else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
      pt.w = document.body.scrollWidth;
      pt.h = document.body.scrollHeight;
    } 
    else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
      pt.w = document.body.offsetWidth;
      pt.h = document.body.offsetHeight;
    }
    return pt;
}
//显示所有的下拉列表框
function showSelectBoxes(){
	selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {selects[i].style.visibility = "visible";	}
}
//隐藏所有的下拉列表框
function hideSelectBoxes(){
	selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {selects[i].style.visibility = "hidden";}
}