How to upload a PDF file from a webpage, get its fields values and render them into the same webpage

I am trying to develop a web page where I want to upload a PDF file from a web page, get the values of its fields then render them into the web page fields using JavaScript. I started with the following code but I can not get the value of the PDF fields. May I ask for a sample code on how to do this

<html>
<head>
<script src="jquery-2.1.4.js"></script>
<script src="jspdf.min.js"></script>
</head>
<body>
<input type="file" id="file-id" name="file_name" onchange="ExtractText();">
<!-- a container for the output -->
<div id="output"></div>
<script>
function ExtractText() {
var input = document.getElementById("file-id");
// Insert get doc field code here
var doc = new jsPDF(input.files[0]);
}
</script>
</body>
</html>