Javascript表单提交有时无效

Question

I am submitting my form during beforeunload event of javascript. It is behaving in a different manner for all the browsers. In chrome 29, if I am closing my browser within 1 minute,then it is hitting the server side action, but if my application is idle for more than 1 minute and then I am closing my browser, then its not hitting the server. Similarly in IE10 and FF20, I cannot stay idle for more than 5 minutes.

<script> 
    function updateServerCMIModel(item) {
        document.forms[0].itemID.value = item;
        formstring = top.window.CPFrame.showCurrentModelState("form");
        document.forms[0].data.value = formstring;
        document.forms[0].nextAction.value = top.window.frames.CPFrame.CPAPI.userEvent;
        document.forms[0].lmsAction.value = "update";
        document.forms[0].submit();
    }
</script>

Is there any way to resolve this issue?

Answer 1

It's a timing issue. You need a way to delay the actual unloading of the page until the form post succeeds. A very typical hack is to throw up a dialogue to the user after posting the form ("Are you sure you want to leave this page?") and hope the user takes a few seconds before clicking.

To do this, simply return a string containing a message of your choice from the event handler, eg

window.onbeforeunload = function(e) {
  doFormPost();
  return 'Dialog text here.';
};

Answer 2

Now the issue is fixed. I have achieved it through Synchronous AJAX call.