How can leading blanks before a statement in PHP code affect the functionality of a download feature?

Leading blanks before a statement in PHP code can cause issues with headers being sent prematurely, which can affect the functionality of a download feature. To solve this issue, make sure there are no leading blanks before any PHP opening tags <?php or any output functions like echo or print. 

&lt;?php
// Corrected PHP code without leading blanks
// Code for downloading a file
$file = &#039;example.pdf&#039;;
if (file_exists($file)) {
    header(&#039;Content-Description: File Transfer&#039;);
    header(&#039;Content-Type: application/pdf&#039;);
    header(&#039;Content-Disposition: attachment; filename=&quot;&#039;.basename($file).&#039;&quot;&#039;);
    header(&#039;Expires: 0&#039;);
    header(&#039;Cache-Control: must-revalidate&#039;);
    header(&#039;Pragma: public&#039;);
    header(&#039;Content-Length: &#039; . filesize($file));
    readfile($file);
    exit;
} else {
    echo &#039;File not found&#039;;
}

Keywords

leading blanks statement PHP code functionality download feature

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