PhpOffice\PhpPresentation\Shape\Drawing\Base64::getData PHP Method

    public function getData()
    {
        return $this->data;
    }

 public function testData()
 {
     $oDrawing = new Base64();
     $this->assertNull($oDrawing->getData());
     $oDrawing->setData($this->imageData);
     $this->assertNotEmpty($oDrawing->getData());
 }