. . . Again, like I and phpsales said, use AJAX. It can send the existing form when the user closes the browser. In other words, AJAX will essentially "click" the logout button when the user closes the browser (not litterally-- it will send the same data to the server, though in a slightly different way, thus causing the same effect; as far as the server is concerned, the user clicked the button). Check out a simple ajax tutorial here. (Not the best tutorial on the web, but if you already know JavaScript, it should be a breeze.)
An example of AJAX taken from the end of the tutorial:
Code:
<html>
<body>
<script type="text/javascript">
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.myForm.time.value=xmlHttp.responseText;
}
}
xmlHttp.open("GET","time.asp",true);
xmlHttp.send(null);
}
</script>
<form name="myForm">
Name: <input type="text"
onkeyup="ajaxFunction();" name="username" />
Time: <input type="text" name="time" />
</form>
</body>
</html>
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