实例：Ajax开发页面聊天系统

七、在线访客统计

客户端：

function OnlineNum()

{

     if(objTimeronline)

     {

     loadXML("get","online.asp?frompage="+frompage+"a&b="+b,OnlineNumOk);

     }

     objTimeronline=window.setTimeout("OnlineNum()",2000) ;

}

function OnlineNumOk(xmlDom) 

{

     if(document.getElementById("minmain"))

     {

document.getElementById("minmain").innerHTML=xmlDom.responseText;

     }

     }

服务端程序：online.asp

<% Response.Charset="gb2312" %>

<% Session.CodePage=936 %>

<!--#include file="conn.asp"-->

<%

Response.addHeader "pragma", "no-cache"

Response.addHeader "cache-control", "private"

Response.CacheControl = "no-cache"

b=request("b")

if instr(b,"Netscape") then

frompage=StreamToStr(request("frompage"))

else

frompage=del1(request("frompage"))

end if

set rs=server.CreateObject("adodb.recordset")

sql="select * from online where frompage='"&frompage&"'"

rs.open sql,conn,1,3

if not rs.bof or not rs.eof then

onlinenum=rs.recordcount

end if

rs.close

set rs=nothing

conn.close

set conn=nothing

response.write("在线"&onlinenum&"人")

%>