anxp

<?php
/**
 * Checks that the file has allowed MIME type.
 *
 * @param $file
 *   A Drupal file object.
 * @param $mimetypes_string
 *   A string with a space separated list of allowed MIME types.
 *
 * @return

anxp

<?php
//Sometimes we need to submit only part of the form. Sure, if form has #required fields, all they will be highlighted with red,
//and form will not be submitted if these elements have no value.
//To workaround this, we can use '#limit_validation_errors' option AND custom submit function for every 'Partial Submit' button.

//Interesting note: when we use '#limit_validation_errors', we will see ALL form fields in _validate function,
//but in _submit function will be visible ONLY elements, included in '#limit_validation_errors' array!!!

//Case 1. The most simple.
//We want to make a 'reset' button, or 'previous step' button, so it must work even if some REQUIRED form elements are empty:

anxp

<?php
function _nxte_redeem_is_email_valid($email) {
  if (empty ($email)) {return false;}

  list($user_name, $mail_domain) = explode('@', $email);

  if (empty($user_name) || empty($mail_domain)) {return false;}

  $is_syntax_ok = (bool) filter_var($email, FILTER_VALIDATE_EMAIL);
  $is_MX_exists = checkdnsrr($mail_domain, 'MX');

anxp

/**
 * This function generates simple table with header row from specified data (tableContent, headerLabels).
 * tableContent is 2-D array with DOM Elements as values:
 * [
 *  0 => [0 => DOM_Obj_1cell_1row, 1 => DOM_Obj_2cell_1row, 2 => DOM_Obj_3cell_1row, ...], <- first row
 *  1 => [0 => DOM_Obj_1cell_2row, 1 => DOM_Obj_2cell_2row, 2 => DOM_Obj_3cell_2row, ...], <- second row
 * ];
 * headerLabels is 1-D array, also with DOM Elements as values (not just strings!);
 * [
 *  0 => DOM_Obj_headerlabel_1, 1 => DOM_Obj_headerlabel_2, ...

anxp

<?php
//This function checks if specified date IS IN acceptable interval from NOW to some moment in the past.
//$date_to_check need to be in classic datetime format, like in mySQL;
//$interval sets like here http://php.net/manual/en/dateinterval.construct.php, but without 'P',
//'P' will be added automatically.
function is_date_acceptable($date_to_check, $interval) {
  $now = new DateTime();
  $interval = 'P'.$interval;
  $min_acceptable_date = $now->sub(new DateInterval($interval));

anxp

<?php

//Array with connection credentials. This is the same structured array like in "settings.local.php" file in your Drupal set up.
$db_connection_data = [
    'host' => 'localhost',
    'database' => 'example_db',
    'username' => 'root',
    'password' => '',
    'driver' => 'mysql',
  ];

anxp

<?php

$db_connection_data = = [
    'host' => 'localhost',
    'database' => 'example_db',
    'username' => 'root',
    'password' => '',
    'driver' => 'mysql',
  ];

anxp

<?php
/**
   * Generate a random string, using a cryptographically secure
   * pseudorandom number generator (random_int)
   *
   * For PHP 7, random_int is a PHP core function
   * For PHP 5.x, depends on https://github.com/paragonie/random_compat
   *
   * @param int $length      How many characters do we want?
   * @param string $keyspace A string of all possible characters

anxp

<?php
/**
 * Function filters out not-allowed symbols from string and return 'cleaned' string.
 * Allowed symbols specified as array of UTF-8 address ranges.
 * When it needs to change allowed range, consider this resource for all UTF-8 characters code sets: https://unicode-table.com/en/blocks/
 * @param string $text input string to filter
 * @param bool $stripTags remove HTML tags or not
 * @param array $allowed_utf8_ranges array with ranges of allowed symbols
 * @return mixed|null|string
 * @throws Exception

anxp

<?php
$form['#tree'] = TRUE;

$form['part_of_the_form'] = [
  '#type' => 'container',
];

$form['part_of_the_form']['field_1'] = [
  '#type' => 'textfield',
  '#title' => 'Field-1',