Writing to file using ajax

Question

I've never really used AJAX before so I'm trying to get familiar. I have an html page:

<html>
<script type="text/javascript" src="jquery-1.12.3.min.js"></script>

<script>
    function write(){
        $.ajax({
        type: 'POST',
        url: "write.php",
        data: "something",
        success: function(result) {
            alert('the data was successfully sent to the server');
        }
        })
    }
</script>

Click to write some stuff
<a href="javascript:write()" class="write">Write</a>
</html>

And the associated write.php file in the same directory:

<?php
error_reporting(E_ALL);
$data = $_POST['data'];
$f = fopen('file.txt', 'w+');
fwrite($f, $data);
fclose($f);
?>

When I click the link, I get the success message, but the file is not created on the server. Not really sure what to investigate. Have confirmed I have write access to the directory

http://php.net/manual/en/function.error-reporting.php and look at your console — Funk Forty Niner, May 11 '16 at 15:58
added the error_reporting line to php. Don't see any errors in the console when hitting the link — Brady forcier, May 11 '16 at 16:01
still no errors after inserting that line. And wouldn't the file still be created even in the data wasn't contained where I'm trying to access it? — Brady forcier, May 11 '16 at 16:06
impossible. tried your code, got back `PHP Notice: Undefined index: data`. check your logs — Funk Forty Niner, May 11 '16 at 16:09
You need to get in the habit of [accepting answers](http://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work) which help you to solve your issues. You'll earn points and others will be encouraged to help you. — Jay Blanchard, May 11 '16 at 16:18

score 3 · Answer 1 · answered May 11 '16 at 16:14

Look, if you're going to use jQuery use it all of the way. First, your link shouldn't have any inline JavaScript.

<a href="#" class="write">Write</a>

When clicked you capture the click of your link event in your main jQuery code by its class (and stop the default behavior of the click):

<script>
    $(document).on('click', '.write', function(event) {
        event.preventDefault();

You're not sending what you think your are sending to the PHP script as the $_POST array expects key / value pairs. Create a key/value pair(s) for your data:

        $.ajax({
        type: 'POST',
        url: "write.php",
        data: {something: 'foo'}, // key value pair created, 'something' is the key, 'foo' is the value

Don't use alert() for troubleshooting., use console.log() instead.

            success: function(result) {
                console.log('the data was successfully sent to the server');
            }
        });
    });
</script>

Now, when you send the data you'll have something in $_POST['something']:

<?php
    error_reporting(E_ALL);
    $data = $_POST['something']; // the key we sent was "something"
    $f = fopen('file.txt', 'w+');
    fwrite($f, $data);
    fclose($f);
?>

Now the text file should contain "foo" because you have actually sent something to the PHP script which can be parsed. The only other thing you need to do is to make sure the PHP script has permissions to open and write to a file on your server.

Writing to file using ajax

1 Answers1