PHP-下载大文件时页面被阻止

Question

I have a download.php page which will be invoked everytime a user clicks "Download" button on my page. The file is around 1 GB. However, the current page got blocked before the file is completely downloaded. Is there a way I can make this an async task so that the user can still use the website while the file is being downloaded to his computer.

Thanks.

Answer 1

If you are using sessions, then before you begin any long running process you should call session_write_close() or you will get blocking site-wide. From the docs there:

Session data is usually stored after your script terminated without the need to call session_write_close(), but as session data is locked to prevent concurrent writes only one script may operate on a session at any time.

So, if you have a long running script that called session_start() and did not call session_write_close() then the result is, any page that needs to access a session now has to wait for the long running script to finish execution before it can begin. Thus, site-wide blocking.

This may or may not solve your issue, because I'm not sure what you mean by "blocking" in your question.

Answer 2

First Create your download links like this :-

<a class="download" href="/myfiles/video/file.pdf"> Dow

nload file.pdf

then in Jquery :

$(document).ready(function(){

   $(document).on('.download', 'click', function(){

       var href = $(this).href;
       $('<iframe />', { src :  href }).appendTo('body');    
       return false; // prevent from default action, can be done with e.preventDefault() also

   }) // __download

}); // __ document ready

This technique use by many big sites like facebook, github etc, and it will not block current page, everything will be working like before but browser will show file save dialog to download file, I did not test this code so there may be some syntex error, Thanks :)