File uploads used to be difficult to implement for developers. Luckily, as web standards have advanced, so have file uploads. AJAX (XMLHttpRequests) now has ubiquitous browser support, and can be safely relied on to handle file uploads. And even better, the new FormData interface allows you to easily grab all of the form’s keys/values in just a couple of lines.
In this post, you’ll learn how to use current AJAX best practices to upload files to a server. The example below supports uploading multiple files in a single request, but the same technique can be used for single-file uploads as well.
Visit: https://blog.filestack.com/thoughts-and-knowledge/ajax-file-upload-formdata-examples/