php and styled html table to pdf - php

Question

i have this code generating a styled table but uses php to grab info for the table from a database.
<form name="pt_list" action="classes/MYPDF.php" method="post"><br/>
<input type="submit" name="pdf" value="Download as PDF">
</form>
<?php
ob_start();
?>
<table id=patients>
<tr>
<th>Pt. username</th>
<th>Pt. number</th>
<th>Full Name</th>
<th>Added on</th>
</tr>
<?php $x=1;
foreach ($users as $patient) {
?> <tr <?php if ($x % 2 == 0) {echo "class='alt'"; } ?>>
<td> <?php echo $patient['username'];?></td>
<td> <?php echo $patient['id'];?></td>
<td> <?php echo $patient['name'];?></td>
<td> <?php echo $patient['joined'];?></td>
</tr>
<?php
$x++;
} ?>
</table>
<?php
$GLOBALS['table'] = ob_get_clean();
$table = $GLOBALS['table'];
?>
i am trying to grab this table and offer it to users to download as a pdf. i tried tcpdf and fpdf but always keep getting cannot send pdf, output already sent. Here is my code for MYPDF.php:
<?php
//============================================================+
// File name : example_003.php
// Begin : 2008-03-04
// Last Update : 2013-05-14
//
// Description : Example 003 for TCPDF class
// Custom Header and Footer
//
// Author: Nicola Asuni
//
// (c) Copyright:
// Nicola Asuni
// Tecnick.com LTD
// www.tecnick.com
// info#tecnick.com
//============================================================+
/**
* Creates an example PDF TEST document using TCPDF
* #package com.tecnick.tcpdf
* #abstract TCPDF - Example: Custom Header and Footer
* #author Nicola Asuni
* #since 2008-03-04
*/
// Include the main TCPDF library (search for installation path).
require_once('../tcpdf/tcpdf.php');
// Extend the TCPDF class to create custom Header and Footer
class MYPDF extends TCPDF {
//Page header
public function Header() {
// Logo
$image_file = K_PATH_IMAGES.'logo_example.jpg';
$this->Image($image_file, 10, 10, 15, '', 'JPG', '', 'T', false, 300, '', false, false, 0, false, false, false);
// Set font
$this->SetFont('helvetica', 'B', 20);
// Title
$this->Cell(0, 15, '<< TCPDF Example 003 >>', 0, false, 'C', 0, '', 0, false, 'M', 'M');
}
// Page footer
public function Footer() {
// Position at 15 mm from bottom
$this->SetY(-15);
// Set font
$this->SetFont('helvetica', 'I', 8);
// Page number
$this->Cell(0, 10, 'Page '.$this->getAliasNumPage().'/'.$this->getAliasNbPages(), 0, false, 'C', 0, '', 0, false, 'T', 'M');
}
}
// create new PDF document
$pdf = new MYPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true, 'UTF-8', false);
// set document information
$pdf->SetCreator(PDF_CREATOR);
$pdf->SetAuthor('Nicola Asuni');
$pdf->SetTitle('TCPDF Example 003');
$pdf->SetSubject('TCPDF Tutorial');
$pdf->SetKeywords('TCPDF, PDF, example, test, guide');
// set default header data
$pdf->SetHeaderData(PDF_HEADER_LOGO, PDF_HEADER_LOGO_WIDTH, PDF_HEADER_TITLE, PDF_HEADER_STRING);
// set header and footer fonts
$pdf->setHeaderFont(Array(PDF_FONT_NAME_MAIN, '', PDF_FONT_SIZE_MAIN));
$pdf->setFooterFont(Array(PDF_FONT_NAME_DATA, '', PDF_FONT_SIZE_DATA));
// set default monospaced font
$pdf->SetDefaultMonospacedFont(PDF_FONT_MONOSPACED);
// set margins
$pdf->SetMargins(PDF_MARGIN_LEFT, PDF_MARGIN_TOP, PDF_MARGIN_RIGHT);
$pdf->SetHeaderMargin(PDF_MARGIN_HEADER);
$pdf->SetFooterMargin(PDF_MARGIN_FOOTER);
// set auto page breaks
$pdf->SetAutoPageBreak(TRUE, PDF_MARGIN_BOTTOM);
// set image scale factor
$pdf->setImageScale(PDF_IMAGE_SCALE_RATIO);
// set some language-dependent strings (optional)
if (#file_exists(dirname(__FILE__).'/lang/eng.php')) {
require_once(dirname(__FILE__).'/lang/eng.php');
$pdf->setLanguageArray($l);
}
// ---------------------------------------------------------
// set font
$pdf->SetFont('times', 'BI', 12);
// add a page
$pdf->AddPage();
// set some text to print
// print a block of text using Write()
$pdf->writeHTML($GLOBALS['table'], true, false, true, false, '');
// ---------------------------------------------------------
//Close and output PDF document
$pdf->Output('example_003.pdf', 'D');
//============================================================+
// END OF FILE
this is the error i get: Notice: Undefined index: table in /Users/Tika/PhpstormProjects/ooplr/classes/MYPDF.php on line 105
TCPDF ERROR: Some data has already been output, can't send PDF file.
Any input would be greatly appreciated.

Answer 1

Notice: Undefined index: table in /Users/Tika/PhpstormProjects/ooplr/classes/MYPDF.php on line 105
This means that $GLOBALS['table'] is undefined, holds no data. What happens when you change the writeHTML row to something like 'test' instead of $GLOBALS['table']?
Are you sure the variable is filled with the table HTML in the first place? Try going to the top of mypdf.php and write var_dump($GLOBALS['table']); exit; after the initial < ?php tag. Does it output anything?
TCPDF ERROR: Some data has already been output, can't send PDF file.
This is due to the fact that you can't generate and output a PDF if you already printed something out in the document. In this case, I think it's a follow on error since an error has been outputed to the document, you can't make it a pdf any longer. It may also have to do with something as stupid as a whitespace character before the initial < ?php.
If I understand the situation correctly, I think your problem is moving the table data from the html file to MYPDF.php. If that's the case, I'd consider an alternative solution:
<form name="pt_list" action="classes/MYPDF.php" method="post"><br/>
<?php foreach ($users as $patient) {
echo '<input type="hidden" name="patients[]" value="'.$patient['id'].'">';
} ?>
<input type="submit" name="pdf" value="Download as PDF">
</form>
This will give you a hidden input field for every patient, and let's you send forth the data to the form target (in this case, mypdf.php). Since I'm using [ ] in the name field, php will recognize many fields can use this name and will make the result an array. In mypdf.php you can now reach this data through the magic variable $_POST['patients']. You can foreach this data or reach the data individually like so: $_POST['patients'][0] ... [1] etc...
You can do the same to get the username, name, joined data through as well, or you can use the ID to fetch the data from the database again. If you get this far, I'm sure you'll figure out the rest on your own.
This is my first response so please let me know if I'm not being helpful, or let me know if there's anything you don't understand.