javascript - "heartbeat"记录器问题

Question

好吧，我发布了一个“烦人的弹出窗口”问题，作为“记录”某人在页面上花费的时间的解决方案，普遍的共识是在计时器上使用 ajax 调用来向服务器报告用户的情况仍在页面上...(下面是我想到的代码)。

我遇到的一个问题是 httRequest 似乎被缓存了...每个返回都显示相同的“时间戳”...

<script type="text/javascript">

var closeMe = 0;
var logMe = 0;

//the window doesn't have focus, do nothing or something that let's them know we're not logging at the moment
function onBlur() {
    ///stop the log interval
    clearInterval ( logMe );  
    //after 2 min of non focus, close it.
    closeMe = setInterval('window.close()',120000); //after 2 min of non focus, close it.
}

//the window has focus... keep logging.
function onFocus(){
    //stop the close counter - in the event to 'blurred' sometime
    clearInterval ( closeMe );  
    //run the AJAX on a schedule - we're doing it every minute - bu tyou can do it as often as you like
    logMe = setInterval('logTime()',60000);
}

//call a script that logs another minute...
function logTime() {
    var xhReq = new XMLHttpRequest();
    xhReq.open("GET", "ajax-on-time-interval.cfm", false);
    xhReq.send(null);

    var serverResponse = xhReq.responseText;
    alert(serverResponse); 
} 

// check for Internet Explorer... IE uses 'onfocusin/out" - everything else uses "onfocus/blur"
if (/*@cc_on!@*/false) {
    document.onfocusin = onFocus;
    document.onfocusout = onBlur;
} else {
    window.onfocus = onFocus;
    window.onblur = onBlur;
}

</script>

“ajax-on-time-interval.cfm”的代码 #现在()#

Answer 1

IE 会缓存 Ajax 请求。为了阻止这种情况，我通常只需在我的请求中添加一个随机变量:

function logTime() {
    var xhReq = new XMLHttpRequest();
    xhReq.open("GET", "ajax-on-time-interval.cfm?random="+Math.random(), false);
    xhReq.send(null);

    var serverResponse = xhReq.responseText;
    alert(serverResponse); 
}

只要您不在后端解析新的“随机”变量，这应该就可以工作:-)