Getting a file with the File API

One of the first things that we will cover is how to use the File API to get a file from the user's computer. There is a good chance you have interacted with the File API on a web page and have not even realized it yet! The API is usually denoted by the Browse or Choose File text located on an input field in the HTML page and often looks something similar to this:

Although the API has been around for quite a while, the one you are probably familiar with is the original specification, dating back as far as 1995. This was the Form-based File Upload in HTML specification that focused on allowing a user to upload a file to a server using an HTML form. Before the days of the file input, application developers had to rely on third-party tools to request files of data from the user. This specification was proposed in order to make a standard way to upload files for a server to download, save, and interact with. The original standard focused entirely on interacting...