gistfile1.php

<?php
        $form = new Form();
 
        $form->setAttribute('method', 'post');
 
        $fieldset1 = new Fieldset('user');
        $fieldset1->setOptions(array(
                      'use_as_base_fieldset' => true
                  ));
 
        $fieldset1->add(array(
            'name'       => 'username',
            'type'       => 'Zend\Form\Element\Text',
            'options'    => array(
                'label' => 'Username1:'
            )
        ));
 
        $form->add($fieldset1);
 
        $form->add(array(
            'name'       => 'submit',
            'type'       => 'Zend\Form\Element\Submit',
            'attributes' => array(
                'value' => 'Speichern'
            )
        ));

        $inputFilter = new InputFilter();
 
        $inputFilter->add(
            array(
                'name'       => 'username',
                'validators' => array(
                    array(
                        'name'    => 'StringLength',
                        'options' => array(
                            'min'     => 5,
                            'max'     => 255,
                            'message' => 'Mindestens 5 und maximal 255 Zeichen lang'
                        )
                    )
                )
            )
        );
 
        $form->setInputFilter($inputFilter);