Writing text to .txt file using PHP - php

Question

So I have page.txt which looks like this:
<textarea name="msg" rows="1"></textarea>
<form id="post" name="post" action="storeText.php" method="post">
<input class="button" type="submit" value="Set news now"/>
</form>
I also have storeText.php which looks like this:
<?php
$filename = 'posts.txt';
$msg = (isset($_POST['msg']) ? $_POST['msg'] : null);
// Let's make sure the file exists and is writable first.
if (is_writable($filename)) {
// In our example we're opening $filename in append mode.
// The file pointer is at the bottom of the file hence
// that's where $somecontent will go when we fwrite() it.
if (!$handle = fopen($filename, 'a')) {
echo "Cannot open file ($filename)";
exit;
}
// Write $somecontent to our opened file.
if (fwrite($handle, $msg) === FALSE) {
echo "Cannot write to file ($filename)";
exit;
}
echo "Success, wrote ($msg) to file ($filename)";
fclose($handle);
} else {
echo "The file $filename is not writable";
}
?>
Now it should write the text onto posts.txt but it always says "Success, wrote () to file...". Notice the empty parenthesis which should have my input.
Any ideas? Thanks!

Answer 1

<textarea name="msg" rows="1"></textarea>
<form id="post" name="post" action="storeText.php" method="post">
<input class="button" type="submit" value="Set news now"/>
</form>
If the textarea is outside of the form block it won't be sent. So your html should look like:
<form id="post" name="post" action="storeText.php" method="post">
<textarea name="msg" rows="1"></textarea>
<input class="button" type="submit" value="Set news now"/>
</form>

Answer 2

Your <textarea> element is outside of your <form> tags.
<textarea>should either go inside the form tags or you need to specify a form attribute to link the input to a form e.g. <textarea form="myForm"> (the latter may not work in older browsers, though, best to put it inside the <form> tag if you can).
That's why your $_POST['msg'] is null