Installtion Steps for mpdf in CodeIgnitor3

mpdf_installation_code_ignitor_3.text

Installations steps for mPDF
1. Check PHp, Codeignioter and Composer Version
    Php      = 7.4.3
    CI3      = 3.1x
    Composer = 2.1x
2. Install composer 
    composer require mpdf/mpdf 

3. While installing mpdf you might get following error (Optional)
    If you are getting any error related to "mikey179/vfsStream" which say capital letters not allowed 
    then you need to open composer.json file and find these line
        "mikey179/vfsstream": "1.1.*",
    and replace like this
        vfsStream -> vfsstream
    After this repeact step 2. 

4. Implementation need to include complete path of autoloader in you controller 
        include('/var/www/html/ci3/vendor/autoload.php');
    Example: 
     public function downloadReceipt()
    {
        try {
            $mpdf = new \Mpdf\Mpdf();
            $data = file_get_contents('/var/www/html/ci3/application/views/demo.html'); // Pass file path           
            $mpdf->WriteHTML($data);
            $mpdf->Output('download.pdf', 'D'); //For Download
            $mpdf->Output(); //For Preview
        } catch (\Mpdf\MpdfException $e) {
            echo $e->getMessage();
        }
    }