[b][show.php][/b]
[code]
<?php 

function showusers() {
include("config.php");
$num = mysql_num_rows($res);

if (!($res = mysql_query ($sql))) {
  trigger_error (mysql_error ());
}
else {
	if($num >= 1) {
		$i = 0;
		while($data = mysql_fetch_assoc($res)) {
			if($i > 0) {
				$userdata .= ", " . $data[$namefield];
	
			} else {
				$userdata = $data[$namefield];
			}
			$i++;
		}
				
	} else {
		$userdata = "Er zijn geen users online";
	}
}
?>
<script type="text/javascript" src="ajax.js"></script>

<div onmouseOver="ajaxFunction();" id="usercontainer">
<?php
echo $userdata;
?>
</div>
<?php
}
?>
[/code]

[b][users.php][/b]
[code]
<?php
//return online-users to ajax
include("config.php");
$num = mysql_num_rows($res);
if (!($res = mysql_query ($sql))) {
  trigger_error (mysql_error ());
}
else {
	if($num >= 1) {
		$i = 0;
		while($data = mysql_fetch_assoc($res)) {
			if($i > 0) {
				$userdata .= ", " . $data[$namefield];
	
			} else {
				$userdata = $data[$namefield];
			}
			$i++;
		}
				
	} else {
		$userdata = "Er zijn geen users online";
	}
}
echo $userdata;

?>
[/code]

[b][ajax.js][/b]
[code]
function ajaxFunction()
  {
  var xmlHttp;
  try
    {
    // Firefox, Opera 8.0+, Safari
    xmlHttp=new XMLHttpRequest();
    }
  catch (e)
    {
    // Internet Explorer
    try
      {
      xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      }
    catch (e)
      {
      try
        {
        xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
      catch (e)
        {
        alert("Your browser does not support AJAX!");
        return false;
        }
      }
    }
    xmlHttp.onreadystatechange=function()
      {
      if(xmlHttp.readyState==4)
        {
        document.getElementById('usercontainer').innerHTML = xmlHttp.responseText;
        }
      }
    xmlHttp.open("GET","users.php",true);
    xmlHttp.send(null);
  }
[/code]

[b][config.php][/b]
[code]
<?php

$dbHost						= ""; 
$dbUser 					= ""; 
$dbPass						= ""; 
$dbName						= ""; 
$namefield					= ""; 

mysql_connect($dbHost, $dbUser, $dbPass) or trigger_error(mysql_error());
mysql_select_db($dbName) or trigger_error(mysql_error());

$qry = "SELECT * FROM users WHERE status = 'online'";

?>
[/code]