PHP - How to use mPDF to merge PDFs

Question

I will start out by saying that I can generate PDFs just fine with mPDF, but for the life of me, I can\'t get it to merge an existing PDF with the PDF it just generated.

Answer 1

I Merge pdfs like this - {all pages in all files}:

$this = Class that extends mPDF class...

function mergePDFFiles(Array $filenames, $outFile)
{
    if ($filenames) {

        $filesTotal = sizeof($filenames);
        $fileNumber = 1;

        $this->SetImportUse(); // this line comment out if method doesnt exist

        if (!file_exists($outFile)) {
            $handle = fopen($outFile, 'w');
            fclose($handle);
        }

        foreach ($filenames as $fileName) {
            if (file_exists($fileName)) {
                $pagesInFile = $this->SetSourceFile($fileName);
                for ($i = 1; $i <= $pagesInFile; $i++) {
                    $tplId = $this->ImportPage($i); // in mPdf v8 should be 'importPage($i)'
                    $this->UseTemplate($tplId);
                    if (($fileNumber < $filesTotal) || ($i != $pagesInFile)) {
                        $this->WriteHTML('');
                    }
                }
            }
            $fileNumber++;
        }

        $this->Output($outFile);

    }

}