var xmlHttp;

function gopage(a)
{ 
xmlHttp=GetXmlHttpObject()
if (xmlHttp==null)
 {
 alert ("Browser does not support HTTP Request")
 return
 }
var url="../ajax/getpage.php"
url=url+"?a="+a+"&b=0";
//document.getElementById("myphoto").innerHTML = "<center><br/><br/><br/><img src='../images/loading.gif'/> <font style='font-size:12px'>下载中，请稍等...</font></center>";
xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("POST",url,true)
xmlHttp.send(null)
}

function stateChanged() 
{ 
	 if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
	 { 
	 	document.getElementById("joke").innerHTML=xmlHttp.responseText;
	 }
}

function GetXmlHttpObject()
{
var xmlHttp=null;
try
 {
 // Firefox, Opera 8.0+, Safari
 xmlHttp=new XMLHttpRequest();
 }
catch (e)
 {
 //Internet Explorer
 try
  {
  xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
  }
 catch (e)
  {
  xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
 }
return xmlHttp;
}