Zend framework 2: class_exists('mPDF') returns true yet new mPDF() fails

Question

I want to use mPDF in a controller as follows (test scenario):

function indexAction() {
    require_once('libraries/mpdf/mpdf.php');
    var_dump(class_exists('mPDF')); //prints true
    $mpdf = new mPDF(); //fails with 'class not found in Application/Controller (current namespace)
}

The class mPDF is declared inside the mpdf.php file and i've checked if the file gets loaded and it does.

Answer 1

To solve this you have to add \ infront of the class name to reset namespace

function indexAction() {
    require_once('libraries/mpdf/mpdf.php');
    var_dump(class_exists('mPDF')); //prints true
    $mpdf = new \mPDF(); //fails with 'class not found in Application/Controller (current namespace)
}

error message is the clue to this

//fails with 'class not found in Application/Controller (current namespace)

I however dont know why the class_exist returns true. It did not do that when i had my class in autoload_classmap.php but when i require_once i got the same problem.

also if you dont want to require_once the php file in the function you can add it to class mapp file at the root of the module

<?php
// Generated by ZF2's ./bin/classmap_generator.php
return array(
    'mPDF'                          => __DIR__ . 'path/to/file/mpdf.php',
);

I do this with PHPMailer