Form doesn't working properly - php

Question

If all inputs are filled, everything works just fine. But if I check just checkbox, the form let me register, no matter I didn't fill all the inputs.
Also if add var_dump to the bottom of the page ( when just checkbox is checked) it says "boolean false " Please help...
<?php
$page_title = 'Registracija'; // Definiše title i h1
$folder = 'registration-db';
if (!file_exists($folder)) {
mkdir($folder, 0777, true);`enter code here`
}
$fajl = $folder . '/registrovani_korisnici.txt';
// Citanje podataka
if (file_exists($fajl)) {
$podaci = file_get_contents($fajl);
$registracija = explode("\n", rtrim($podaci)); //Vracanje података iz baze
}
$errors = false;
//Obrada forme i provera podataka
if (!empty($_POST)) { //ako nije prazna promenljiva
//Provera da li su podaci unešeni
if (empty($_POST['user_name'])) { //radi
$errors[] = 'Niste upisali ime i prezime!<br>';
}
if (empty($_POST['user_email'])) { //radi
$errors[] = 'Niste uneli E-mail!<br>';
}
if (filter_var($_POST['user_email'], FILTER_VALIDATE_EMAIL) === false) {// Izbacio !empty($_POST['user_email']) &&
$errors[] = 'Nije validna email adresa!<br>';
}
if (empty($_POST['user_password'])) { //radi
$errors[] = 'Niste uneli lozinku!<br>';
}
if (strlen($_POST[]) <= 5) { //radi
$errors[] = 'Lozinka mora da ima više od 5 karaktera!<br>';
}
if (empty($_POST['user_password2'])) { //radi
$errors[] = 'Niste potvrdili lozinku!<br>';
}
if ($_POST['user_password'] !== $_POST['user_password2']) {
$errors[] = 'Lozinka mora da bude ista u oba pokušaja!';
}
if (empty($_POST['day']) || empty($_POST['month']) || empty($_POST['year'])) { //radi
$errors[] = 'Niste uneli ispravan datum!<br>';
}
if (empty($_POST['check'])) { //radi
$errors[] = 'Niste prihvatili uslove korišćenja!<br>';
}
/*if (date('Y') - $_POST['year'] < 15) {
$errors[] = 'Nemate dovoljno godina, da biste se registrovali!<br>';
}*/ //Problem kada se ne definiše vrednost $_POST['year']!!!!!
else {
// Data forwarding
extract($_POST);
// Name
// Skidanje tagova - Zbog bezbednosti!!!
$user_name = strip_tags($user_name);
//Pretvaranje u mala slova
$user_name = strtolower($user_name);
//Pretvaranje prvih slova u velika (Ime Prezime)
$user_name = ucwords($user_name);
// Čišćenje Email-a
$user_email = strip_tags($user_email);
//Čišćenje Lozinke
$user_password = strip_tags($user_password);
//Čišćenje Lozinke2
$user_password2 = strip_tags($user_password2);
/*html_entity_decode();
htmlentities();*/
$podaci .= $user_name . '#!$!#' . $user_email . '#!$!#' . $user_password . '#!$!#' . $user_password2 . '#!$!#' . $day . '.' . $month . '.' . $year . '#!$!#' . PHP_EOL;
//Zapisivanje u fajl
file_put_contents($fajl, $podaci);
header('Location: registracija.php?sent=1');
}
}
?>
<?php include 'inc/header.php'; //include header?>
<!-- Prikazivanje greške-->
<?php if ($errors !== false) : ?>
<p>GREŠKA: </p>
<?php foreach ($errors as $error) : ?>
<p><?php echo $error; ?></p>
<?php endforeach; ?>
<?php endif; ?>
<?php if (isset($_GET['sent']) && $_GET['sent'] == 1): ?>
<h2>Uspešno ste registrovani! Hvala.</h2>
<?php else : ?>
<!-- Form -->
<form action="" method="post">
<p>
<input type="text" name="user_name" placeholder="Ime i prezime">
</p>
<p>
<input type="email" name="user_email" placeholder="E-mail">
</p>
<p>
<input type="password" name="user_password" placeholder="Lozinka">
</p>
<p>
<input type="password" name="user_password2" placeholder="Ponovite lozinku">
</p>
<h2>Datum rodjenja</h2>
<select name="day">
<option selected disabled>Dan</option>
<?php for ($i = 1; $i <= 31; $i++) : ?>
<option> <?php echo $i; ?> </option>
<?php endfor; ?>
</select>
<select name="month">
<option selected disabled>Mesec</option>
<?php for ($i = 1; $i <= 12; $i++) : ?>
<option> <?php echo $i; ?> </option>
<?php endfor; ?>
</select>
<select name="year">
<option selected disabled>Godina</option>
<?php
$start = date("Y");
$end = date("Y") - 100;
?>
<?php for ($i = $start; $i >= $end; $i--) : ?>
<option> <?php echo $i; ?> </option>
<?php endfor; ?>
</select>
<br>
<br>
<input type="checkbox" name="check"> Prihvatam uslove korišćenja
<p>
<button>Registrujte se</button>
</p>
</form>
<?php endif; ?>
<!-- Form END -->
<?php include 'inc/footer.php'; //include footer?>

Answer 1

First of all, you might want to turn you if statements into a if - else if - else chain. In your situation, if last if statement returns false, your former validations become void.
if (empty($_POST['day'])) {
//Validation
}
else if (empty($_POST['year'])) {
//Validation
}
else if (empty($_POST['check'])) {
//Validation
}
// Other validations
else {
}
Also, you should add a value to your checkbox like this:
<input type="checkbox" name="check" value="1" />
This way, if it's checked, it will post a value.
In your current situation, even if checkbox is checked, you don't send any value and your last if statement evaluates to false.
EDIT:
To display all missing fields at once, you just change your else statement into another if-else statements like this:
if (empty($_POST['user_name'])) {
$errors[] = 'Niste upisali ime i prezime!<br>';
}
if (empty($_POST['check'])) {
$errors[] = 'Niste prihvatili uslove korišćenja!<br>';
}
//Other validations
if($errors) {
//Show errors
}
else{
// Data forwarding
// Same as your former else statement
}

Answer 2

It's a small logical error. Your else block is only associated with your last if block. As a result, else will be entered if the last if block is not executed.
If $_POST['check'] is not empty that is if the condition inside the lastif block` returns false then the else will be entered and registration gets completed.
What could you do to get around this?
Use a flag. Declare a variable as $c=1;. We will change the value of this variable to 0 if any if block is entered.
$c=1;
if (empty($_POST['user_name'])) { //radi
$errors[] = 'Niste upisali ime i prezime!<br>';
$c=0;
}
if (empty($_POST['user_email'])) { //radi
$errors[] = 'Niste uneli E-mail!<br>';
$c=0;
}
if (filter_var($_POST['user_email'], FILTER_VALIDATE_EMAIL) === false) {// Izbacio !empty($_POST['user_email']) &&
$errors[] = 'Nije validna email adresa!<br>';
$c=0;
}
if (empty($_POST['user_password'])) { //radi
$errors[] = 'Niste uneli lozinku!<br>';
$c=0;
}
if (strlen($_POST[]) <= 5) { //radi
$errors[] = 'Lozinka mora da ima više od 5 karaktera!<br>';
$c=0;
}
if (empty($_POST['user_password2'])) { //radi
$errors[] = 'Niste potvrdili lozinku!<br>';
$c=0;
}
$if ($_POST['user_password'] !== $_POST['user_password2']) {
$errors[] = 'Lozinka mora da bude ista u oba pokušaja!';
$c=0;
}
$if (empty($_POST['day']) || empty($_POST['month']) || empty($_POST['year'])) { //radi
$errors[] = 'Niste uneli ispravan datum!<br>';
$c=0;
}
$if (empty($_POST['check'])) { //radi
$errors[] = 'Niste prihvatili uslove korišćenja!<br>';
$c=0;
}
elseif ($c==1)
{
//CODE
}
else if block will only be entered if $c==1 is true.
You could also use if-elseif-else ladder.
OR:
You can use the required attribute in each input tag to force the users to fill that particular field before submitting.
eg:
<input type="email" name="user_email" Placeholder="Email" required>
Add the required attribute in each input tag to stop the form from getting submitted if a field is not entered.
For example, in the above case, the form wouldn't get submitted if email-id is not entered.