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<h1>FAQ</h1> | |
<ul> | |
<li><b>1.</b> <a href='#q1'>What's exactly the license of FPDF? Are there any usage restrictions?</a></li> | |
<li><b>2.</b> <a href='#q2'>I get the following error when I try to generate a PDF: Some data has already been output, can't send PDF file</a></li> | |
<li><b>3.</b> <a href='#q3'>Accented letters are replaced by some strange characters like é.</a></li> | |
<li><b>4.</b> <a href='#q4'>I try to display the Euro symbol but it doesn't work.</a></li> | |
<li><b>5.</b> <a href='#q5'>I try to display a variable in the Header method but nothing prints.</a></li> | |
<li><b>6.</b> <a href='#q6'>I have defined the Header and Footer methods in my PDF class but nothing shows.</a></li> | |
<li><b>7.</b> <a href='#q7'>I can't make line breaks work. I put \n in the string printed by MultiCell but it doesn't work.</a></li> | |
<li><b>8.</b> <a href='#q8'>I use jQuery to generate the PDF but it doesn't show.</a></li> | |
<li><b>9.</b> <a href='#q9'>I draw a frame with very precise dimensions, but when printed I notice some differences.</a></li> | |
<li><b>10.</b> <a href='#q10'>I'd like to use the whole surface of the page, but when printed I always have some margins. How can I get rid of them?</a></li> | |
<li><b>11.</b> <a href='#q11'>How can I put a background in my PDF?</a></li> | |
<li><b>12.</b> <a href='#q12'>How can I set a specific header or footer on the first page?</a></li> | |
<li><b>13.</b> <a href='#q13'>I'd like to use extensions provided by different scripts. How can I combine them?</a></li> | |
<li><b>14.</b> <a href='#q14'>How can I open the PDF in a new tab?</a></li> | |
<li><b>15.</b> <a href='#q15'>How can I send the PDF by email?</a></li> | |
<li><b>16.</b> <a href='#q16'>What's the limit of the file sizes I can generate with FPDF?</a></li> | |
<li><b>17.</b> <a href='#q17'>Can I modify a PDF with FPDF?</a></li> | |
<li><b>18.</b> <a href='#q18'>I'd like to make a search engine in PHP and index PDF files. Can I do it with FPDF?</a></li> | |
<li><b>19.</b> <a href='#q19'>Can I convert an HTML page to PDF with FPDF?</a></li> | |
<li><b>20.</b> <a href='#q20'>Can I concatenate PDF files with FPDF?</a></li> | |
</ul> | |
<ul id='answers'> | |
<li id='q1'> | |
<p><b>1.</b> <span class='question'>What's exactly the license of FPDF? Are there any usage restrictions?</span></p> | |
FPDF is released under a permissive license: there is no usage restriction. You may embed it | |
freely in your application (commercial or not), with or without modifications. | |
</li> | |
<li id='q2'> | |
<p><b>2.</b> <span class='question'>I get the following error when I try to generate a PDF: Some data has already been output, can't send PDF file</span></p> | |
You must send nothing to the browser except the PDF itself: no HTML, no space, no carriage return. A common | |
case is having extra blank at the end of an included script file.<br> | |
<br> | |
The message may be followed by this indication:<br> | |
<br> | |
(output started at script.php:X)<br> | |
<br> | |
which gives you exactly the script and line number responsible for the output. If you don't see it, | |
try adding this line at the very beginning of your script: | |
<div class="doc-source"> | |
<pre><code>ob_end_clean();</code></pre> | |
</div> | |
</li> | |
<li id='q3'> | |
<p><b>3.</b> <span class='question'>Accented letters are replaced by some strange characters like é.</span></p> | |
Don't use UTF-8 with the standard fonts; they expect text encoded in windows-1252. | |
You can perform a conversion with iconv: | |
<div class="doc-source"> | |
<pre><code>$str = iconv('UTF-8', 'windows-1252', $str);</code></pre> | |
</div> | |
Or with mbstring: | |
<div class="doc-source"> | |
<pre><code>$str = mb_convert_encoding($str, 'windows-1252', 'UTF-8');</code></pre> | |
</div> | |
In case you need characters outside windows-1252, take a look at tutorial #7 or | |
<a href="http://www.fpdf.org/?go=script&id=92" target="_blank">tFPDF</a>. | |
</li> | |
<li id='q4'> | |
<p><b>4.</b> <span class='question'>I try to display the Euro symbol but it doesn't work.</span></p> | |
The standard fonts have the Euro character at position 128. You can define a constant like this | |
for convenience: | |
<div class="doc-source"> | |
<pre><code>define('EURO', chr(128));</code></pre> | |
</div> | |
</li> | |
<li id='q5'> | |
<p><b>5.</b> <span class='question'>I try to display a variable in the Header method but nothing prints.</span></p> | |
You have to use the <code>global</code> keyword to access global variables, for example: | |
<div class="doc-source"> | |
<pre><code>function Header() | |
{ | |
global $title; | |
$this->SetFont('Arial', 'B', 15); | |
$this->Cell(0, 10, $title, 1, 1, 'C'); | |
} | |
$title = 'My title';</code></pre> | |
</div> | |
Alternatively, you can use an object property: | |
<div class="doc-source"> | |
<pre><code>function Header() | |
{ | |
$this->SetFont('Arial', 'B', 15); | |
$this->Cell(0, 10, $this->title, 1, 1, 'C'); | |
} | |
$pdf->title = 'My title';</code></pre> | |
</div> | |
</li> | |
<li id='q6'> | |
<p><b>6.</b> <span class='question'>I have defined the Header and Footer methods in my PDF class but nothing shows.</span></p> | |
You have to create an object from the PDF class, not FPDF: | |
<div class="doc-source"> | |
<pre><code>$pdf = new PDF();</code></pre> | |
</div> | |
</li> | |
<li id='q7'> | |
<p><b>7.</b> <span class='question'>I can't make line breaks work. I put \n in the string printed by MultiCell but it doesn't work.</span></p> | |
You have to enclose your string with double quotes, not single ones. | |
</li> | |
<li id='q8'> | |
<p><b>8.</b> <span class='question'>I use jQuery to generate the PDF but it doesn't show.</span></p> | |
Don't use an AJAX request to retrieve the PDF. | |
</li> | |
<li id='q9'> | |
<p><b>9.</b> <span class='question'>I draw a frame with very precise dimensions, but when printed I notice some differences.</span></p> | |
To respect dimensions, select "None" for the Page Scaling setting instead of "Shrink to Printable Area" in the print dialog box. | |
</li> | |
<li id='q10'> | |
<p><b>10.</b> <span class='question'>I'd like to use the whole surface of the page, but when printed I always have some margins. How can I get rid of them?</span></p> | |
Printers have physical margins (different depending on the models); it is therefore impossible to remove | |
them and print on the whole surface of the paper. | |
</li> | |
<li id='q11'> | |
<p><b>11.</b> <span class='question'>How can I put a background in my PDF?</span></p> | |
For a picture, call Image() in the Header() method, before any other output. To set a background color, use Rect(). | |
</li> | |
<li id='q12'> | |
<p><b>12.</b> <span class='question'>How can I set a specific header or footer on the first page?</span></p> | |
Just test the page number: | |
<div class="doc-source"> | |
<pre><code>function Header() | |
{ | |
if($this->PageNo()==1) | |
{ | |
//First page | |
... | |
} | |
else | |
{ | |
//Other pages | |
... | |
} | |
}</code></pre> | |
</div> | |
</li> | |
<li id='q13'> | |
<p><b>13.</b> <span class='question'>I'd like to use extensions provided by different scripts. How can I combine them?</span></p> | |
Use an inheritance chain. If you have two classes, say A in a.php: | |
<div class="doc-source"> | |
<pre><code>require('fpdf.php'); | |
class A extends FPDF | |
{ | |
... | |
}</code></pre> | |
</div> | |
and B in b.php: | |
<div class="doc-source"> | |
<pre><code>require('fpdf.php'); | |
class B extends FPDF | |
{ | |
... | |
}</code></pre> | |
</div> | |
then make B extend A: | |
<div class="doc-source"> | |
<pre><code>require('a.php'); | |
class B extends A | |
{ | |
... | |
}</code></pre> | |
</div> | |
and make your own class extend B: | |
<div class="doc-source"> | |
<pre><code>require('b.php'); | |
class PDF extends B | |
{ | |
... | |
} | |
$pdf = new PDF();</code></pre> | |
</div> | |
</li> | |
<li id='q14'> | |
<p><b>14.</b> <span class='question'>How can I open the PDF in a new tab?</span></p> | |
Just do the same as you would for an HTML page or anything else: add a target="_blank" to your link or form. | |
</li> | |
<li id='q15'> | |
<p><b>15.</b> <span class='question'>How can I send the PDF by email?</span></p> | |
As for any other file, but an easy way is to use <a href="https://github.com/PHPMailer/PHPMailer" target="_blank">PHPMailer</a> and | |
its in-memory attachment: | |
<div class="doc-source"> | |
<pre><code>$mail = new PHPMailer(); | |
... | |
$doc = $pdf->Output('S'); | |
$mail->AddStringAttachment($doc, 'doc.pdf', 'base64', 'application/pdf'); | |
$mail->Send();</code></pre> | |
</div> | |
</li> | |
<li id='q16'> | |
<p><b>16.</b> <span class='question'>What's the limit of the file sizes I can generate with FPDF?</span></p> | |
There is no particular limit. There are some constraints, however: | |
<br> | |
<br> | |
- There is usually a maximum memory size allocated to PHP scripts. For very big documents, | |
especially with images, the limit may be reached (the file being built in memory). The | |
parameter is configured in the php.ini file. | |
<br> | |
<br> | |
- The maximum execution time allocated to scripts defaults to 30 seconds. This limit can of course | |
be easily reached. It is configured in php.ini and may be altered dynamically with set_time_limit(). | |
<br> | |
<br> | |
You can work around the memory limit with <a href="http://www.fpdf.org/?go=script&id=76" target="_blank">this script</a>. | |
</li> | |
<li id='q17'> | |
<p><b>17.</b> <span class='question'>Can I modify a PDF with FPDF?</span></p> | |
It's possible to import pages from an existing PDF document thanks to the | |
<a href="https://www.setasign.com/products/fpdi/about/" target="_blank">FPDI</a> extension. | |
Then you can add some content to them. | |
</li> | |
<li id='q18'> | |
<p><b>18.</b> <span class='question'>I'd like to make a search engine in PHP and index PDF files. Can I do it with FPDF?</span></p> | |
No. But a GPL C utility does exist, pdftotext, which is able to extract the textual content from a PDF. | |
It's provided with the <a href="https://www.xpdfreader.com" target="_blank">Xpdf</a> package. | |
</li> | |
<li id='q19'> | |
<p><b>19.</b> <span class='question'>Can I convert an HTML page to PDF with FPDF?</span></p> | |
Not real-world pages. But a GPL C utility does exist, <a href="https://www.msweet.org/htmldoc/" target="_blank">HTMLDOC</a>, | |
which allows to do it and gives good results. | |
</li> | |
<li id='q20'> | |
<p><b>20.</b> <span class='question'>Can I concatenate PDF files with FPDF?</span></p> | |
Not directly, but it's possible to use <a href="https://www.setasign.com/products/fpdi/demos/concatenate-fake/" target="_blank">FPDI</a> | |
to perform that task. Some free command-line tools also exist: | |
<a href="https://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/" target="_blank">pdftk</a> and | |
<a href="http://thierry.schmit.free.fr/spip/spip.php?article15" target="_blank">mbtPdfAsm</a>. | |
</li> | |
</ul> | |
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