如何知道将带有文件的表单提交给iframe是否失败

I built a photo submission using iframe. The thing is that how to know if file fails to submit due to newtwork delay or disconnection for example. Is there an event for such a thing? or just if it takes too long I just cancel it if there is a way to cancel it. I know when it is done as the reply from server is a javascript function that gets loaded as recevied but what to do if I do not receive anything!

<form action="iframe.php" target="my-iframe" method="post">

    <label for="text">Some text:</label>
    <input type="file" name="file" id="file">

    <input type="submit" value="post">

</form>

<iframe name="my-iframe" src="iframe.php"></iframe>

 <script>
     function img_upload_done(opn,img,photo_number){ // opn holds boolen if img uploaded succefully
           //do something
     }
 </script>

        <?php
        //getting the directory of the this file
           $destination_path = getcwd().DIRECTORY_SEPARATOR;
            $name = rand (100,1000);
           $result = 0;
           $filename=$_FILES['file']['name'];
           $ext = pathinfo($filename, PATHINFO_EXTENSION) ; 
         // setting up the directory of the file uploaded
           $target_path = $destination_path . $name .".". $ext;

         //making sure the file has been uploaded in the specified directory
           if(@move_uploaded_file($_FILES['file']['tmp_name'], $target_path)) {
              $result = 1;
           }

           sleep(0);
        ?>
        <script language="javascript" type="text/javascript">
           window.top.window.img_upload_done(<?php echo $result.",\"".$name .".". $ext."\",".$_POST["photo-number"]; ?>);
        </script>







         <?php
         //This function separates the extension from the rest of the file name and returns it
         function findexts ($filename) {
            $filename = strtolower($filename) ;
             $exts = split("[/\\.]", $filename) ;
             $n = count($exts)-1;
             $exts = $exts[$n];
             return $exts;
         }
         //This applies the function to our file
         ?>

You could make use of the window.postMessage() function, to send a failure or success message to your page.

It could look something like this in your main page:

window.addEventListener("message", receiveMessage, false);

function receiveMessage(event)
{
  var origin = event.origin || event.originalEvent.origin; // For Chrome, the origin property is in the event.originalEvent object.
  if (origin !== "http://www.your-url.com")
    return;

  // ...
}

And in the iFrame you would do something like this, after the file is saved (or it failed):

// where to send messages with postMessage
var target_origin = 'http://www.your-url.com';

parent.postMessage( {'success': 'true'}, target_origin );

More infos: https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage