如何使用PHP、jQuery和AJAX上传多个文件

I have designed a simple form which allows the user to upload files to the server. Initially the form contains one 'browse' button. If the user wants to upload multiple files, he needs to click on the "Add More Files" button which adds another 'browse' button in the form. When the form is submitted, the file upload process is handled in 'upload.php' file. It works perfectly fine for uploading multiple files. Now I need to submit the form by using jQuery's '.submit()' and send a ajax ['.ajax()'] request to the 'upload.php' file to handle the file upload. I have designed a simple form which allows the