Form API Validation - Module

This module drastically increase the validation power of Drupal Form API (FAPI).
You can use the existent filters and rules or create your own. Is up to you.

Why not Validation API ?

The Validation API module is focused on Drupal end users and not module developers. There is no documentation so I guess that you can only set validations on admin interface.
So FAPI Validation come to give you, developer, more facility on your development process.
If you have any consideration to do, fill free for it at #637598: Merge with validation API?

Modules using FAPI Validation

• Clientside Validation

Available Rules

Rule	Usage	Description
numeric	numeric	Must contains only numbers.
length	length[<total>] length[<min>, <max>]
chars	chars[<char 1>, <char 2>, ..., <char N>]	Accept only specified characters.
email	email	Valid email
url	url url[absolute]	Valid URL. If absolute parameter is specified, the field value must have to be a full URL.
ipv4	ipv4	Valid IPv4
alpha_numeric	alpha_numeric	Accept only Alpha Numeric characters
alpha_dash	alpha_dash	Accept only Alpha characters and Dash ( - )
digit		Checks wheter a string consists of digits only (no dots or dashes).
decimal	decimal decimal[<digits>,<decimals>]
regexp	regexp[/^regular expression$/]	PCRE Regular Expression

Available Filters

Filter	Description
numeric	Remove all non numeric characters.
trim	Remove all spaces before and after value.
uppercase	Transform all characters to upper case.
lowercase	Transform all characters to lower case.

Usage

Example:

<?php//...
$form['myfield'] = array(
  '#type' => 'textfield',
  '#title' => 'My Field',
  '#required' => TRUE,
  '#rules' => array(
    'email',
    'length[10, 50]',
    array('rule' => 'alpha_numeric', 'error' => 'Please, use only alpha numeric characters at %field.')
  ),
  '#filters' => array('trim', 'uppercase')
);
//...?>

Developer

If any of this rules was what you need, you can use your own with hook_fapi_validation_rules and hook_fapi_validation_filters.

<?php/**
* Implementation of hook_fapi_validation_rules
*/function mymodule_fapi_validation_rules() {
  return array(
    'rule_name' => array(
      'callback' => 'mymodule_validation_rule_name',
      'error_msg' => 'Invalid value for %field'
    ),
  );
}
/**
* Implementation of hook_fapi_validation_filters
*/function mymodule_fapi_validation_filters() {
  return array(
    'filter_name' => array(
      'callback' => 'mymodule_validation_filter_name',
    ),
  );
}

function mymodule_validation_rule_name($value) {
  if (preg_match('/^[a-z]+$/', $value)) {
    return TRUE;
  }
  else {
    return FALSE;
  }
}

function mymodule_validation_filter_name($value) {
  return preg_replace('/\d+/', '', $value);
}?>

And now you can use on your Form API.

<?php//...
$form['myfield'] = array(
  '#type' => 'textfield',
  '#title' => 'Email',
  '#required' => TRUE,
  '#rules' => array('rule_name'),
  '#filters' => array('trim', 'filter_name')
);
//...?>

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