Validate URI In Form Fields With Zend Framework Custom Validator

Introduction to Zend Framework

Zend Framework is an open source, object-oriented web application framework implemented in PHP 5 and licensed under the New BSD License. Zend Framework provides many components like Zend_Form, Zend_Controller, Zend_Validate, Zend_Filter to build web secure and robust applications fairly faster.

To know more about Zend Framework visit the following websites:

Zend_Form:

Zend_Form official reference guide is available at http://framework.zend.com/manual/en/zend.form.html

Zend_Form simplifies form creation and handling in your web application. Taking advantage of Zend_Filter and Zend_Validate you can filter and validate your form fields. At the time of writing this article 19 validation classes are shipped with Zend Framework. I came across a situation where I had to write a custom class to validate URIs. To write the custom URI validator I made use of Zend_Uri which aids in manipulating and validating Uniform Resource Identifiers (URIs). In particular I used Zend_Uri::check() function to validate the URI in question.

BV_Validate_Uri - Custom Validator To Check Whether A Given URI Is Valid

In order to use BV_Validate_Uri you must have set up your application to use Zend Framework. You must also know how to use Zend_Form to validate the form fields.

Create the directory BV under your Zend Framework library directory. Also create the directory Validate under BV. Create a file by name Uri.php and copy the PHP code to it.

mkdir library/BV
mkdir library/BV/Validate
vi library/BV/Validate/Uri.php
Copy the below PHP code and save the file


<?php
require_once 'Zend/Validate/Abstract.php';
require_once 'Zend/Uri.php';


class BV_Validate_Uri extends Zend_Validate_Abstract
{
    const MSG_URI = 'msgUri';

    protected $_messageTemplates = array(
        self::MSG_URI => "Invalid URI",
    );

    public function isValid($value)
    {
        $this->_setValue($value);

        //Validate the URI
        $valid = Zend_Uri::check($value);
        
        //Return validation result TRUE|FALSE   
        if ($valid)  {
            return true;
        } else {
            $this->_error(self::MSG_URI);
            return false;
        
        }

    }
}

?>

Now we have created a reusable URI validator. You can use this URI validator in all your forms. Below is an example of the BV_Validate_Uri usage with Zend_Form.


<?php

 $website = $form->createElement('text', 'website');
            $website->setLabel('Website URL');
            $website->addValidator(new BV_Validate_Uri());
?>

That is all you need to do to add the BV_Validate_Uri to your form field. When the form is submitted the element is validated by BV_Validate_Uri. In summary, you just have to add one line to add the custom URI validator.


<?php
            $website->addValidator(new BV_Validate_Uri());
?>

I hope this article has helped you to validate URI in your form fields.