function sAlert(str){ 
   var msgw,msgh,bordercolor; 
   msgw=550;//提示窗口的宽度 
   msgh=375;//提示窗口的高度 
   titleheight=25; //提示窗口标题高度 
   bordercolor="#0094c3";//提示窗口的边框颜色 
   titlecolor="#0094c3";//提示窗口的标题颜色 
  
   var sWidth,sHeight; 
   sWidth=document.body.offsetWidth; 
   sHeight=screen.height; 
   var bgObj=document.createElement("div"); 
   bgObj.setAttribute('id','bgDiv'); 
   bgObj.style.position="absolute"; 
   bgObj.style.top="0"; 
   bgObj.style.background="#777"; 
   bgObj.style.filter="progid:DXImageTransform.Microsoft.Alpha(style=3,opacity=25,finishOpacity=75"; 
   bgObj.style.opacity="0.6"; 
   bgObj.style.left="0"; 
   bgObj.style.width=sWidth + "px"; 
   bgObj.style.height=sHeight + "px"; 
   bgObj.style.zIndex = "10000"; 
   document.body.appendChild(bgObj); 
    
   var msgObj=document.createElement("div") 
   msgObj.setAttribute("id","msgDiv"); 
   msgObj.setAttribute("align","center"); 
   msgObj.style.background="white"; 
   msgObj.style.border="1px solid " + bordercolor; 
   msgObj.style.position = "absolute"; 
   msgObj.style.left = "50%"; 
   msgObj.style.top = "30%"; 
   msgObj.style.font="12px/1.6em Verdana, Geneva, Arial, Helvetica, sans-serif"; 
   msgObj.style.marginLeft = "-225px" ; 
   msgObj.style.marginTop = -75+document.documentElement.scrollTop+"px"; 
   msgObj.style.width = msgw + "px"; 
   msgObj.style.height =msgh + "px"; 
   msgObj.style.textAlign = "center"; 
   msgObj.style.lineHeight ="25px"; 
   msgObj.style.zIndex = "10001"; 
    
   var title=document.createElement("h4"); 
   title.setAttribute("id","msgTitle"); 
   title.setAttribute("align","right"); 
   title.style.margin="0"; 
   title.style.padding="3px"; 
   title.style.background=bordercolor; 
   title.style.filter="progid:DXImageTransform.Microsoft.Alpha(startX=20, startY=20, finishX=100, finishY=100,style=1,opacity=75,finishOpacity=100);"; 
   title.style.opacity="0.75"; 
   title.style.border="1px solid " + bordercolor; 
   title.style.height="18px"; 
   title.style.font="12px Verdana, Geneva, Arial, Helvetica, sans-serif"; 
   title.style.color="white"; 
   title.style.cursor="pointer"; 
   title.innerHTML="关闭"; 
   title.onclick=function(){ 
          document.body.removeChild(bgObj); 
          document.getElementById("msgDiv").removeChild(title); 
          document.body.removeChild(msgObj); 
        } 
   document.body.appendChild(msgObj); 
   document.getElementById("msgDiv").appendChild(title); 
   var txt=document.createElement("p"); 
   txt.style.margin="1em 0" 
   txt.setAttribute("id","msgTxt"); 
   txt.innerHTML="<iframe src=ly.htm width=100% height=350px frameborder=0 scrolling=no ></iframe>"; 
   document.getElementById("msgDiv").appendChild(txt); 
}