PHP Email Subscription, cannot post php file - php

Question

Hey I have some trouble with my email subscription I'm trying to log into a textfile.
<!-- Signup Form -->
<form id="signup-form" action="form.php" method="post">
<input type="email" name="email" id="email" placeholder="Email Address" />
<input type="submit" value="Sign Up" />
</form>
Here's my PHP code:
<?php
if(empty($_POST['submit']) === false) {
$email = htmlentities(strip_tags($_POST['email']));
$logname = 'email.txt';
$logcontents = file_get_contents($logname);
if(strpos($logcontents,$email)) {
die('You are already subscribed.');
} else {
$filecontents = $email.',';
$fileopen = fopen($logname,'a+');
$filewrite = fwrite($fopen,$filecontents);
$fileclose = fclose($fileopen);
if(!$fileopen or !$filewrite or !$fileclose) {
die('Error occured');
} else {
echo 'Your email has been added.';
}
}
}
?>
I keep getting Cannot POST /form.php eventho the php file is at that path, someone knows what I'm possibly doing wrong? I'm quit noob at this :(

Answer 1

First of all add name attribute to your submit button, as in POST you will not get the form value of "submit" and your code will never go further
<form id="signup-form" action="form.php" method="post">
<input type="email" name="email" id="email" placeholder="Email Address" />
<input type="submit" name="submit" value="Sign Up" />
</form>
Now in your php code, you just need to check $_POST['submit'] in if condition and you have also done a typo, you have used a variable $fopen which is not defined, change that.
<?php
if($_POST['submit']) {
$email = htmlentities(strip_tags($_POST['email']));
$logname = 'email.txt';
$logcontents = file_get_contents($logname);
if(strpos($logcontents,$email)) {
die('You are already subscribed.');
} else {
$filecontents = $email.',';
$fileopen = fopen($logname,'a+');
$filewrite = fwrite($fileopen,$filecontents);
$fileclose = fclose($fileopen);
if(!$fileopen or !$filewrite or !$fileclose) {
die('Error occured');
} else {
echo 'Your email has been added.';
}
}
}
?>