How to force a PDF to be displayed in the browser

Question

I have a sequence of PDF files that I can link normally, only as soon as I click on one of them it downloads, and I need the PDF to be displayed in the browser itself. I tried to use this on my link but it didn’t help:

target="_blank"

I cannot let the user download directly in any way. How to resolve this issue?

Answer 1

As far as I know how Pdfs are not native web pages is the browser that decides what to do with them. That is why the browser has to be configured to open using some plugin or internal viewer as in firefox for example.

Or else try this

header("Content-Type: application/pdf");
header('Content-Disposition: inline; "nome_do_arquivo.pdf"');

Answer 2

As already mentioned by Ivan Nack, this will depend on the browser, there is how to manipulate the header Content-Disposition, but it will depend on how the browser will handle the file, as there is how to configure the browser to always download the file or if the browser does not handle natively with PDF, it is used plugins like Adobe Reader.

As said by bfavaretto in comment, a way to do this is to convert each page of the PDF file into image and display it, this is how Google should do (I believe), a way to do this in PHP is by using ImageMagick.

Follow an example taken from from here:

$arquivoPDF = 'demo.pdf';
$imagem = 'demo.jpg';
$img = new imagick();

$img->setResolution(200,200); // Isto é importante para dar uma saída de boa qualidade, caso contrário, o texto pode não ser claro  
$img->readImage("{$arquivoPDF}[0]"); // Lê a primeira página do PDF, o número entre [] indica a página
$img->scaleImage(800, 0);            // Reduz as dimensões
$img->setImageFormat('jpg');         // Define novo formato
$img = $img->flattenImages();        // Isso é necessário para imagens com transparência, que irá produzir um fundo branco para regiões transparentes
$img->writeImages($imagem, false);   // Salva a imagem

---

Another alternative, now in Javascript, is to use a renderer like the pdf.js, that does not require third party applications. There is a demonstration here.

---

Finally, there is also how to use the Google viewer to do this what you want, for example:

<iframe src="http://docs.google.com/gview?
 url=http://infolab.stanford.edu/pub/papers/google.pdf&embedded=true"
 style="width:600px; height:500px;" frameborder="0">
</iframe>

DEMO

Answer 3

I was having a similar difficulty following the solution I found giving the two options view in the browser or Download:

<?php
function varSet($VAR) { return isset($_GET[$VAR]) ? $_GET[$VAR] : ""; }
$action = varSet("action");
$pasta = base64_decode(varSet('pasta'));

//Lista dos arquivos que nao serão listados
$denyFiles = array(".htaccess","thumbs.db");

if ($action == "download") {
    $file = base64_decode(varSet("file"));
        header("Content-disposition: attachment; filename=\"".basename($file)."\"");
    readfile(".$file");
    exit;
}
 if ($action == "embed") {
    $file = base64_decode(varSet("file"));
        header("Content-Type: application/pdf");
    readfile(".$file");
    exit;
}
?>
<?php
$pasta = '/arquivos';
$arquivos = "$user->cod_func".'  '.utf8_decode($_POST['select_mes']).' de '.$_POST['select_ano'].'.pdf';
$filename = 'arquivos/'.$arquivos;


if (file_exists($filename)) {
?>  
Download do Arquivo: <a href="?action=download&file=<?php echo base64_encode("$pasta/$arquivos"); ?>"><?php echo $_POST['select_mes'].' '.$_POST['select_ano']; ?></a>
<br><br>
Vizualizar: <a href="?action=embed&file=<?php echo base64_encode("$pasta/$arquivos"); ?>"><?php echo $_POST['select_mes'].' '.$_POST['select_ano']; ?></a>
<br>

<?php
} else {
    echo "Não existe holerith no mês selecionado";
}
?>