title: How to get the output of a php file into a variable using mPDF
body: <p>I'm using mPDF library to provide pdf files. </p>
  
  <p>Assume that I have a file named <code>facture.php</code> that contains :</p>
  
  <ul>
  <li><p>an image in the header</p></li>
  <li><p>a table in the body</p></li>
  <li><p>an image in the footer of the file</p></li>
  </ul>
  
  <p>And another file named <code>convert_HTML2PDF.php</code> that will provide the pdf output of the first file.</p>
  
  <p>I would like to get the output of the facture file that is interpreted into a variable and output it as a pdf file without visualising in the browser. </p>
  
  <p>How can I do that and use the output inside the convert_HTML2PDF.php?</p>