[Resolved] headers and output buffering

PapRika

In this code when action == convert there are some things that happen. The only important thing is that when that action is sent, the headers there must do their work; like sending ABA.jpg to the client. This allready works (after experimentating with ob_start() and ob_flush(). The problem is, after downloading the file is not readable (it has size 29 kb when downloaded)
When I use these 4 header codes in a blank php page it worls but not in combination with this code::


<?php ob_start(); $image="motor.jpg";echo"


<!DOCTYPE HTML PUBLIC '-//W3C//DTD HTML 4.01 Transitional//EN'>
<html>
<head>
<title>Untitled Document</title>

<link href='../../../Documents%20and%20Settings/Henk%20Jan/Mijn%20documenten/I-Bank/smarteye.css' rel='stylesheet' type='text/css'>
</head>

<body>

<table width='771' border='0' cellpadding='0' cellspacing='0'>
  <!--DWLayoutTable-->
  <tr>
    <td height='22' colspan='4' valign='top'><!--DWLayoutEmptyCell-->&nbsp;</td>
    <td width='181'>&nbsp;</td>
    <td width='251'></td>
  </tr>
  <tr>
    <td height='248' colspan='5' align='center' valign='top'><img src='$image' width='339' height='248' align='absmiddle'></td>
    <td></td>
  </tr>
  <tr>
    <td width='158' height='32' valign='middle' class='titel'>Origineel bestand:</td>
    <td colspan='3' valign='middle'>$image</td>

<td align='center' valign='middle'> <input type='submit' name='Submit' value='Download'></td>
    <td></td>
  </tr>
  <tr>
    <td height='32' valign='middle' class='titel'>Converteer extensie</td>

<form action='$PHP_SELF' method='post'>
<input type ='hidden' name= 'action' value='convert'>

 <td colspan='3' valign='top'><select name ='format'>
<option value='GIF'>GIF</option>
<option value='JPG'>JPG</option>
<option value='PNG'>PNG</option>
<option value='TIFF'>TIF</option>
<option value='PDF'>PDF</option>
<option value='MPEG'>MPEG</option>
<option value='EPS'>EPS</option>
<option value='PICT'>PICT</option>
<option value='AVI'>AVI</option>
<option value='PSD'>PSD</option>
<option value='HTML'>HTML</option>
<option value='TXT'>TXT</option>
</select></td>
    <td align='center' valign='middle'> <input type='submit' name ='convert' value='converteer'></td>
    <td></td>

</form>

 <tr>
    <td height='80' colspan='2' valign='top'><table width='100%' border='1' cellpadding='0' cellspacing='0' bordercolor='#CCCCCC'>
        <!--DWLayoutTable-->
        <tr>
          <td height='16' colspan='2' align='center' valign='top' class='titel'>Web-conversie
            (72 DPI)</td>
        </tr>
        <tr>
          <td width='138' height='31' align='center' valign='middle'>
<form action='print $PHP_SELF; ?>' method='post'>
<input type ='hidden' name= 'action' value='convert_72'>


 <select name='con_format'>
              <option value='JPG'>JPG</option>
              <option value='PDF'>PDF</option>
            </select></td>
          <td width='112' align='center' valign='middle'> <select name='con_res'>
              <option>640 * 480</option>
              <option>800 * 600</option>
              <option>1024*768</option>
              <option>1400 *1050</option>
              <option>thumbnail</option>
              <option>pasfoto</option>
            </select></td>
        </tr>
        <tr>
          <td height='33' colspan='2' align='center' valign='middle'> <input type='submit' name='Sconvert_72' value='Convert72'></td>
        </tr>
      </table></td>
    <td width='15'>&nbsp;</td>
    <td colspan='2' valign='top'><table width='100%' border='1' cellpadding='0' cellspacing='0' bordercolor='#CCCCCC'>
        <!--DWLayoutTable-->
        <tr align='center'>
          <td height='19' colspan='2' valign='top' class='titel'> Print -conversie
            (144 DPI)</td>
        </tr>
        <tr>
          <td width='129' height='30' align='center' valign='middle'> <select name='select3'>
            </select></td>
          <td width='126' align='center' valign='middle'> <select name='select5'>
            </select></td>
        </tr>
        <tr align='center' valign='middle'>
          <td height='34' colspan='2'> <input type='submit' name='Submit32' value='Submit'></td>
        </tr>
      </table></td>
    <td></td>
  </tr>
  <tr>
    <td height='730'>&nbsp;</td>
    <td width='92'>&nbsp;</td>
    <td>&nbsp;</td>
    <td width='74'>&nbsp;</td>
    <td></td>
    <td></td>
  </tr>
</table>
</body>
</html>";?>
<?php ob_start();
$error1= "echo <script>alert ('Bestand niet meer aanwezig')</script>";
$error2= "echo <script>alert ('Origineel bestand gelijk aan bestand dat u wilt converteren')</script>";
$confirm1="Bestand succesvol verzonden";


$ext = $format;
$gebruiker="gebruker";
$time=time();


if ($_POST['action'] == "convert") {





	$convert=`convert  $image $time.$format`;
	$bestandsnaam= $time.".$format";
	ob_flush();
	header('Content-type: image/jpg');
	header('Content-Disposition: attachment; filename="aba.jpg"');
	readfile('aba.jpg');
	}
	?>

dopey

You won't want to be echoing out the HTML when your action=='convert'. You'll need a switch or if statement to avoid doing that. e.g.

switch( $_POST['action'] )
{
    default:
          /* HTML goes here */
          break;

case 'convert':
      /* image manipulation and output here */
      break;
}

PapRika

That works fine, BUT!!
When I open the page I allready get "headers allready sent"

The rest works good. Is there a solution for thid?

PapRika

sorry I forgtot the break.
Thanks very much!!

robinjohn

I think it's complaining because you can only send headers once, which you're triggering when you echo all of that stuff to the browser.
Convert it to the form dopey suggests, put it at the start of your code and make sure you don't echo anything before you do the image manipulation bit.
hope that helps.

PapRika

yes that's wise to do, unfortunally I want to put also an IF statment (which ckecks if the file still exists) before I use headers. That brings me again header errors 🙂

ob_start() and ob_flush() won't help me I think

dopey

Hi,

If the image no longer exists when doing the convert, you may want to return a 404 error code (i.e. tells the browser it doesn't exist), which won't cause header errors.
e.g.

if( file_exists('myfile.jpg') ) {
    /* convert and send image as normal */
} else {
    header("HTTP/1.0 404 Not Found"); 
}