When Stackoverflow Sends You in the Wrong Direction (processing file input)
https://stackoverflow.com/questions/2805977/how-do-i-call-a-javascript-function-after-selecting-a-file-from-the-select-file I have a file input element < input type = "file" id = "fileid" > How do I call a JavaScript function after selecting a file from the dialog window and closing it? Yikes! No answer marked right and the most upvoted says : jQuery ("input#fileid") .change (function () { alert (jQuery(this) .val ()) }); I say : OMG All you need to do is <input type="file" onchange="calledFunction()"> FYI, to use the Duke Javascript Library , in your HTML (say in Codepen) : <script src="http://www.dukelearntoprogram.com/course1/common/js/image/SimpleImage.js"> </script> What they didn't do a terrific job of covering in the course (or their documentation) : whether SimpleImage objects can be passed to/from functions? Ans : Yes, just do var name_of_var = function_that_returns_SimpleImage(args...