How can i do this right? PHP5 Form validation - php

Question

I'm trying to set my first steps into the OO PHP world. What I'm trying to do is make a class that validates my form input. I know what input fields I need in my entire website and want to make a switch, to do the right thing based on the input field. Lets say we have the input field named 'email', and we have a form for that etc...
First, what I want to do is try to read the $_post names with array_key() function, based on that I have a switch.
Here is my code:
public function __construct ( $var ) {
$this->arraykeys = array_keys($var);
$this->error = false;
$this->message = array();
}
public function check() {
foreach ($this->arraykeys as $i => $value)
{
switch ($value)
{
case 'email' :
$checkmail = new checkEmail($_POST);
$checkmail->chkEmail($_POST['email']);
if ($checkmail->chkEmail($_POST['email']) == false)
{
array_push($this->message, 'Cannot validate emailadres');
}
break;
}
}
// print_r($this->field);
}
The check works, but somehow the message array stays empty after an error!
I tried everything, but I just can't get it on to the screen!
Please help!
Thanks!!

Answer 1

Before you make use of OOP you actually need to have some of the more basic objects that enable you to let your form processing come to live, for example object oriented validation of form fields within PHP superglobals with error messages:
Just exemplary:
// defining the interfaces and classes of the form values and validation, form field
// and fields
Interface FormValue
{
public function getValue();
}
interface FormValueValidator
{
/**
* #param FormValue $value
* #return bool
*/
public function validate(FormValue $value);
}
class NamedFormValue implements FormValue
{
private $name;
private $value;
public function __construct(array $data, $name, $default = null)
{
$this->name = $name;
$this->value = isset($data[$name]) ? $data[$name] : $default;
}
public function getValue()
{
return $this->value;
}
public function getName()
{
return $this->name;
}
}
class EmailValidator implements FormValueValidator
{
public function validate(FormValue $value)
{
$result = filter_var((string) $value->getValue(), FILTER_VALIDATE_EMAIL);
return is_string($result);
}
}
class FormFieldFactory
{
/**
* #param $name
* #param array $field
* #return FormField
*/
public function create($name, array $field)
{
$validatorClass = sprintf('%sValidator', #$field['validator']);
$validator = new $validatorClass;
$formField = new FormField($name);
$formField->setValidator($validator);
$formField->setErrorMessage($field['error_msg']);
return $formField;
}
}
class FormField
{
private $name;
/**
* #var FormValueValidator
*/
private $validator;
private $errorMessage;
/**
* #var FormValue
*/
private $value;
public function __construct($name)
{
$this->name = $name;
}
public function setValidator(FormValueValidator $validator)
{
$this->validator = $validator;
}
public function isValid()
{
return $this->validator->validate($this->value);
}
public function setErrorMessage($errorMessage)
{
$this->errorMessage = $errorMessage;
}
public function getErrorMessage() {
return $this->errorMessage;
}
public function setValue(FormValue $value)
{
$this->value = $value;
}
/**
* #return FormValue
*/
public function getValue()
{
return $this->value;
}
}
class FormFields extends IteratorIterator
{
private $fieldFactory;
private $invalidFields;
public function __construct(array $definitions, $fieldFactory)
{
parent::__construct(new ArrayIterator($definitions));
$this->fieldFactory = $fieldFactory;
}
public function current()
{
$name = $this->getInnerIterator()->key();
$definition = $this->getInnerIterator()->current();
return $this->fieldFactory->create($name, $definition);
}
public function valid()
{
return $this->getInnerIterator()->valid();
}
/**
* #param array $data
* #return bool true on success, false on validation error
*/
public function validateOn(array $data)
{
$this->invalidFields = array();
foreach($this as $name => $field) {
/* #var $field FormField */
$value = new NamedFormValue($data, $name);
$field->setValue($value);
$valid = $field->isValid();
$valid || ($this->invalidFields[$name] = $field);
}
return 0 === count($this->invalidFields);
}
/**
* #return FormField[]
*/
public function getInvalidFields()
{
return $this->invalidFields;
}
}
// defining the form in array notation:
$form = array(
'fields' => array(
'email' => array(
'validator' => 'Email',
'error_msg' => 'Cannot validate emailadress',
),
),
);
// processing the form validation
$messages = array();
$fields = new FormFields($form['fields'], new FormFieldFactory());
$fields->validateOn($_POST)
foreach ($fields->getInvalidFields() as $field) {
$messages[] = $field->getErrorMessage();
}
var_dump($messages);
Exemplary output:
array(1) {
[0]=>
string(27) "Cannot validate emailadress"
}

Answer 2

Try this instead :
public function check()
{
foreach ($this->arraykeys as $i => $value)
{
switch ($value)
{
case 'email' :
$checkmail = new checkEmail($_POST);
$checkmail->chkEmail($_POST['email']);
if ($checkmail->chkEmail($_POST['email']) == false)
{
$this->message[] = 'Cannot validate emailadres';
}
break;
}
}
print_r($this->message);
}
Also be sure your property is set to public.
Are you sure $checkmail->chkEmail() is getting false and is working well ?