Validate php form fail - php

Question

This code works fine in seperated file named form.php, but when i paste it to
wordpress theme page it does not even validate form and not even send mail of course. Why is there no any action after i clikced submit button in wordpress theme?
Anyone can help me to solve problem?
get_header();
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$nameError = $mailError = $messageError = '';
function validate($data){
if(empty($data)){
return false;
}else{
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
}
//Validate name input
if(!validate($_POST['name'])){
$nameError = 'Polje ime je obavezno.';
}else{
if (!preg_match("/^[a-zA-Z ]*$/",$_POST['name'])) {
$nameError = "Polje moze sadrzavati samo slova i razmak";
}
}
//Validate email input
if(!validate($_POST['email'])){
$mailError = 'Polje email je obavezno';
}else{
if (!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) {
$mailError = "Nevazeća email adresa";
}
}
//Validate message textarea
if(!validate($_POST['message'])){
$messageError = 'Molimo unesite poruku';
}
if(empty($nameError) && empty($mailError) && empty($messageError)){
//Create the body
$body = "Ime: {$_POST['name']}\n\nPoruka: {$_POST['message']}";
//Make it no longer than 70 characters long
$body = wordwrap($body, 70);
//Send the mail
mail('example#example.com', 'Contact Form Submission',
$body,
"From: {$_POST['email']}");
//Print a message
echo '<p><em>Thank you for contacting me. I will reply some day.
</em></p>';
}else{
echo '<p style="font-weight: bold; color: #C00">Please fill out
the
form completley.</p>';
}
}
HTML Code that is placed in same file as php validation
<section class="contact-img">
<div class="container-fluid">
<div class="row">
<?php the_post_thumbnail(); ?>
</div>
</div>
</section>
<section class="contact">
<div class="container">
<div class="row">
<?php dynamic_sidebar('contact-page'); ?>
<div class="col-md-12">
<h4 class="col-xs-12 text-center"><strong>Ostavite
poruku</strong></h4>
</div>
</div>
</div>
<div class="container">
<div class="row">
<div class="col-xs-10 col-xs-offset-1 col-sm-6 col-sm-offset-3">
<form method="POST" action="<?php echo
htmlspecialchars($_SERVER["PHP_SELF"]);?>">
<div class="form-group">
<input type="text" class="form-control" name="name"
value="" placeholder="Ime">
<div><?php if(isset($nameError)) echo $nameError; ?>
</div>
</div>
<div class="form-group">
<input type="text" class="form-control" name="email"
value="" placeholder="E-mail">
<div><span class="error"><?php if(isset($mailError))
echo $mailError; ?></span></div>
</div>
<div class="form-group">
<textarea class="form-control" name="message" rows="3"
placeholder="Poruka"></textarea>
<div><span class="error"><?php
if(isset($messageError)) echo $messageError; ?></span></div>
</div>
<input class="btn btn-default" type="button" name="button"
value="Pošalji">
</form>
</div>
</div>
</div>
</section>

Answer 1

You have a syntax error (white page of death, if error reporting is off)
$nameError = 'Polje moze sadrzavati samo slova i razmak;
Should be:
$nameError = 'Polje moze sadrzavati samo slova i razmak';
Another thing that might get you is your name validation Regex is to simple, it doesn't account for things like Jane Doe-Smith, or J o h n S m i t h or j or even '', an empty string.
I would use something like this:
if(!preg_match("/^([a-z]+)\s+(?:([a-z]+)\s+)?([-a-z]+)$/i" , $_POST['name'])){
$nameError = 'Polje moze sadrzavati samo slova i razmak;
}
Regex:
([a-z]+) matches a though z (first 2 capture groups)
\s+ matches one or more space
(?...) non-capture group ? optionally, middle name
([-a-z]+) matches - and a though z (for hyphenated last names)
\i case insensitive flag.
Regex Test
Test cases:
John Smith {match}
John E Smith {match}
Jane J Doe-Smith {match}
John {no match}
Which is still a small sample size, but should cover most English names ( not sure what language this is Polje moze).
I once dated a girl many many years ago with a hyphenated last name ... lol.
The last thing is to turn on display errors and set error reporting to a value like E_ALL (for development). I'd say use ini_set('display_errors', '1') and error_reporting() but they won't catch syntax errors in the same file (generally).