Passing variables to fpdf - pdf

Question

I have a problem with passing variables to fpdf. First script is getting post text sent to filtering class, the class is returning filtered POST-s as a 2 element array. First script looks like this:
include('service.php');
include('pdf.php');
$pdf_filter = new Pdf_filter;
$filter = $pdf_filter->pdfFilter();
var_dump($filter);
extract($filter);
I'm extracting $filter array to get variables from it (filtering script is creating variables of the POST that are sent and I can echo them so I don't know if this is even necessary).
The second script looks like this:
require('E:\Xampp\php\fpdf181\fpdf.php');
$pdf = new FPDF();
$pdf->AddPage();
$pdf->SetFont('Arial','B',12);
$pdf->Cell(195,5, $tytul, 0,1,'C');
$pdf->Cell(195,5, $petycja, 0,1,'C');
$pdf->Output();
and I'm getting this error:
Notice: Undefined variable: tytul in E:\Xampp\htdocs\php\bazy_danych\obiektowe\my\pdf.php on line 10
Notice: Undefined variable: petycja in E:\Xampp\htdocs\php\bazy_danych\obiektowe\my\pdf.php on line 11
Fatal error: Uncaught exception 'Exception' with message 'FPDF error: Some data has already been output, can't send PDF file' in E:\Xampp\php\fpdf181\fpdf.php:271
Stack trace: #0 E:\Xampp\php\fpdf181\fpdf.php(1063): FPDF->Error('Some data has a...')
#1 E:\Xampp\php\fpdf181\fpdf.php(999): FPDF->_checkoutput()
#2 E:\Xampp\htdocs\php\bazy_danych\obiektowe\my\pdf.php(12): FPDF->Output()
#3 E:\Xampp\htdocs\php\bazy_danych\obiektowe\my\test.php(3): include('E:\\Xampp\\htdocs...')
#4 {main} thrown in E:\Xampp\php\fpdf181\fpdf.php on line 271
How should I pass the variables? Interesting: it works if I use the unfiltered $_POST with the following code:
require('E:\Xampp\php\fpdf181\fpdf.php');
$pdf = new FPDF();
$pdf->AddPage();
$pdf->SetFont('Arial','B',12);
$pdf->Cell(195,5, $_POST['tytul'], 0,1,'C');
$pdf->Cell(195,5, $_POST['petycja'], 0,1,'C');
$pdf->Output();
EDIT: I will post the initial form and filtering function:
Form:
<form action="test.php" method="POST">
Wpisz tytuł petycji (35 znaków):<br>
<input type="text" name="tytul" maxlength="35" size="35" placeholder="Tytuł petycji" required><br>
Wpisz treść petycji (500 znaków):<br>
<textarea name="petycja" maxlength="500" rows="4" cols="50" placeholder="Treść petycji" required></textarea><br>
<input type="submit" value="Napisz petycje">
</form>
Filtering function:
class Pdf_filter{
protected $title;
protected $text;
public function pdfFilter(){
if (isset($_POST)){
foreach ($_POST as $key => $val) {
$filterVal = strip_tags($val);
$filterVal = htmlspecialchars($filterVal);
$filterVal = stripslashes($filterVal);
$filterVal = str_replace("\\", "", $filterVal);
$filter = array($key => $filterVal);
foreach ($filter as $key => $val) {
echo "[$$key]";
echo "$val<br>";
${$key} = $val;
}
}
if(!preg_match("/^[\sa-zA-ZĄĆĘŁŃÓŚŹŻąćęłńóśźż0-9-_,.:\'?()]+$/", $tytul)){
echo "Niedozwolone znaki $tytul!";
exit();
}
elseif(!preg_match("/^[\sa-zA-ZĄĆĘŁŃÓŚŹŻąćęłńóśźż0-9-_,.:\'?()]+$/", $petycja)){
echo "Niedozwolone znaki $petycja!";
exit();
}
else{
return $filter = array('tytul'=>$tytul,'petycja'=>$petycja);
}
}
else{
echo "Proszę wypełnić wszytskie pola!";
}
}
}

Answer 1

Well I am dumb. The problem was related with class variables. Code that happened to work for me:
class Pdf extends FPDF{
protected $filter;
protected $tytul;
protected $petycja;
public function __construct($filter){
$this->filter = extract($filter);
$this->tytul = $tytul;
$this->petycja = $petycja;
}
public function tytul(){
return $this->tytul;
}
public function petycja(){
return $this->petycja;
}
public function dokument(){
parent::__construct();
$this->AddPage();
$this->SetFont('Arial','B',15);
$this->Cell(195,5, $this->tytul, 0,1,'C');
$this->Cell(195,5, $this->petycja, 0,1,'C');
$this->Output();
}
}
Now I need to think of a way to display polish symbols in fpdf and line breaks (but that maybe done with text editor isntead of just textbox).