Noob Noob - 26 days ago 9
jQuery Question

File encryption using CryptoJS - Client side

I am trying to encrypt all files within a folder located on client side. I have the below code, but getting an error. I am not entirely sure about the error.

ERROR: Uncaught TypeError: Cannot read property 'length' of undefined(…) at line 16 in html.

index.html

<!DOCTYPE html>
<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type" />
<title>Get Directory</title>
<script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="assets/js/aes.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$("#file-input").on("change", function(e){
var thefiles = e.target.files;
var reader = new FileReader();
$.each(thefiles, function(i, item){
var thefile = item;
reader.onload = function(){
var encrypted = CryptoJS.AES.encrypt(thefile, '12334');
};
reader.readAsDataURL(thefile);
$("#thelist").append("FILES: " + thefile.name + "<br />");;
});
});
});
</script>
</head>
<body>
<input type="file" id="file-input" webkitdirectory="" directory="">
<div id="thelist"></div>
</body>
</html>

Answer

Read all comments

<!DOCTYPE html>
<html>
<head>
    <meta content="text/html; charset=utf-8" http-equiv="Content-Type" />
    <title>Get Directory</title>
    <!-- Update your jQuery version??? -->
    <script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
    <script src="assets/js/aes.js"></script>
    <script> // type="text/javascript" is unnecessary in html5

    // Short version of doing `$(document).ready(function(){`
    // and safer naming conflicts with $
    jQuery(function($) { 

        $('#file-input').on('change', function() {

            // You can't use the same reader for all the files
            // var reader = new FileReader

            $.each(this.files, function(i, file) {

                // Uses different reader for all files
                var reader = new FileReader

                reader.onload = function() {
                    // reader.result refer to dataUrl
                    // theFile is the blob... CryptoJS wants a string...
                    var encrypted = CryptoJS.AES.encrypt(reader.result, '12334')
                }

                reader.readAsDataURL(file)
                $('#thelist').append('FILES: ' + file.name + '<br>')
            })
        })
    })
    </script>
</head>
<body>
    <input type="file" id="file-input" webkitdirectory="" directory="">
    <div id="thelist"></div>
</body>
</html>

btw, browsers has a modern standard Crypto lib built in... Maybe try using that instead? and if necessary use a polyfill?

Comments