How do I read in a local text file with javascript?

Question

I am trying to use to select a file locally and read the text in it line by line to interpret it. My program is meant to read a text file and read questions from it to make a test taking program. The file should not be uploaded, and only read locally. It is okay if the solution only works on chrome and firefox.

I have tried looking through many things, but so far what I seem to see is that it is not possible for security reasons, or it is but it doesn't work properly. I

This is my current code: http://pastebin.com/uKvEfvZZ

Hiya, this might help: stackoverflow.com/questions/7466387/… ; cheers! — Tats_innit
– Tats_innit, Commented Mar 18, 2012 at 6:10

xdazz · Accepted Answer · 2012-12-01 23:56:07Z

5

Here is a demo.

html:

<input type="file" id="fileinput" multiple />

js:

function readMultipleFiles(evt) {
    //Retrieve all the files from the FileList object
    var files = evt.target.files;

    if (files) {
        for (var i = 0, f; f = files[i]; i++) {
            var r = new FileReader();
            r.onload = (function (f) {
                return function (e) {
                    var contents = e.target.result;
                    alert(contents);
                };
            })(f);
            r.readAsText(f);
        }
    } else {
        alert("Failed to load files");
    }
}
document.getElementById('fileinput').addEventListener('change', readMultipleFiles, false);

edited Dec 1, 2012 at 23:56

answered Mar 18, 2012 at 6:13

xdazz

161k38 gold badges255 silver badges278 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user1276567 Over a year ago

I used code similar to this before, apparently I had some errors. This helped alot, thank you!

Michael Over a year ago

Great example written in pure JS! Thanks

Nemoy · Accepted Answer · 2012-03-18 06:10:00Z

4

Use HTML5 file API. It allows you to select and read files locally.

answered Mar 18, 2012 at 6:10

Nemoy

3,4471 gold badge17 silver badges14 bronze badges

4 Comments

user1276567 Over a year ago

That is actually what I had tried before. It didn't seem to work properly.

Nemoy Over a year ago

It is supported in modern browsers only. Check xdazz's demo

user1276567 Over a year ago

this works, but not locally (on chrome atleast). I forgot to update everyone on that. When i tried it on a webhost it was perfectly fine.

pilau Over a year ago

@user1276567 for accessing local files in Chrome you must start Chrome with this switch: chrome --disable-web-security

Collectives™ on Stack Overflow

How do I read in a local text file with javascript?

2 Answers 2

2 Comments

4 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

4 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related