// JavaScript Document
function chg(id_num){ 
var oa = document.getElementById(id_num); 
var ob = document.getElementsByName("showHide_a"); 
if(oa.style.display == "block"){ 
oa.style.display = "none"; 
ob.innerHTML = "<img src='images/lxhfWyhfBtn.gif' alt='我要回复' />"; 
}else{ 
oa.style.display = "block"; 
ob.innerHTML = "<img src='images/lxhfQxhfBtn.gif' alt='取消回复' />"; 
} 
return false; 
}