function showpic(ob,obwidth,obheight) 
{
var allbox=document.getElementById("allbox") 
if(allbox!==null) 
{
	document.body.removeChild(allbox) 
}
var screenwidth=(document.body.scrollWidth) 
var newlayer=document.createElement("div") 
newlayer.style.cssText="width:"+screenwidth+"px;text-align:center;position:absolute; top:220px; left:0; z-index:560;clear:both;"
newlayer.setAttribute("id","allbox") 

var ahref=document.createElement("a") 
ahref.setAttribute("href","#") 
ahref.style.cssText="border:none;"

var pic=document.createElement("img") 
pic.setAttribute("src",ob) 
pic.style.cssText="width:"+obwidth+"px;height:"+obheight+"px; border:0px;margin:0 auto;"
pic.onclick=function() 
{
document.body.removeChild(newlayer) 
}

var pic_box=document.createElement("div") 
pic_box_width=obwidth+20
pic_box_height=obheight+10
pic_box.style.cssText="width:"+pic_box_width+"px;height:"+pic_box_height+"px; margin:0 auto; "
ahref.appendChild(pic) 
pic_box.appendChild(ahref) 
newlayer.appendChild(pic_box) 
document.body.appendChild(newlayer) 

}