STANDARD.md

Formatting and Standards

Character Encoding

UTF-8 (without Byte Order Mark a.k.a. BOM)

Indentation

Indentation of logic should be 2 whitespace characters.

Level 1
  Level 2
    Level 3
      Level 4

TABs should not be used.

Level 1
	Level 2
		Level 3
			Level 4

Indentation of comments is subtracted one level:

// This is a comment
  echo 'Hello World!';

Indentation of code after opening a PHP tag:

<?php
  dosomething();
  ..
?>

Line Breaks

Do not use more than one empty line for separating logic.

Naming of Variables and Elements

Don't make up shortenings. Always use full words unless they are annoyingly long. Don't mix languages, use english only for code and comments. Don't mix lower and upper cases.

Correct:

  $customer_address
  $customer['address']

Incorrect:

  $custaddr // Weird shortenings
  $kund_adress // Foreign language
  $customerAddress // Mixed cases
  $customer['customer_address'] // Duplicate prefix

Naming of CSS classes and IDs

<div id="box-hello" class="box white">

Encapsulating Parameters - Singe-Quotes vs. Double-Quotes

Single quote characters should be used for PHP and javascript code unless parsing data or simply inconvenient.

Use double quotes for all HTML element parameters in accordance with SGML.

Correct:

echo '<a href="http://www.site.com">Hello World</a>';

database::query("select * from Table where id = 'string'");

<img src="" />

$('.myclass').html();

When it can be compromised:

echo "Hello y'all";
echo "Hello $name\r\n";

$('input[name="field"]').val();

Incorrect:

echo "Hello World!";

<img src='' />

Translating Variables

When translating variables in strings we use strtr to avoid cryptic coding.

Correct:

$string = strtr('Text with %b %a', array('%a' => $a, '%b' => $b));

Incorrect:

$string = sprintf('Text with %2$s %1$s', $b, $a);

File Naming

The filename of the files must be all lowercase characters and contain no more than 31 characters to be Apple/Mac compatible. Word separation by underscore.

Name files that are grouped with a prefix e.g:

box_background_red.png
box_background_green.png
box_background_blue.png

File Extensions

Non-HTML PHP output scripts should be named by their output format extension like the following:

.php
.json.php

Included files should be named:

.inc.php
.json.inc.php

Beginning & Ending PHP Logic

When starting PHP logic, the tag should be written as "<?php", not in the short form of "<?".

Inline PHP code:

<?php echo "Hello World!"; ?>

PHP Code Block:

<?php
  echo "Hello World!";
  ...
?>

Avoid ending ?> at the end of file

PHP Variable Scope

Do not EVER use register_globals as we use PHP Superglobals.

$_GET['variable']
$_POST['variable']
$_COOKIE['variable']
$_SESSION['variable']

No Variable Duplication

Unless there is a certain need to duplicate variables, no variable duplication should be used:

Incorrect:

  $name = $_POST['name'];
  $trimmed_name = trim($name);

Correct:

$_POST['name'] = trim($_POST['name']);

PHP Arrays

Inline arrays

do_something(array('this', 'that'));

Defining a variable with more than a handful of values

$variable = array(
  'this',
  'that',
  ...
  'last', // <-- Make note of the ending coma
);

Outputting Line Breaks

Use the PHP_EOL constant for outputting line breaks in PHP.

Correct:

echo 'Hello World!' . PHP_EOL
   . 'This is a new row';

For emails use \r\n accoarding to RFC standrard

echo "Hello World!\r\nThis is a new row";

PHP Class Variables and Methods

class my_class {
  private $_data;
  public $data;

  private function _my_private_method() {
  }

  public function my_public_method() {
  }
}

Database Queries in PHP

Database queries should be line breaked, indented, and presented in lowercases.

database::query(
  "select * from ". DB_TABLE_NAME ."
  where id = '". (int)$integrer ."'
  ". (isset($string) ? "and string = '". database::input($string) ."'" : "") ."
  limit 1;"
);

Unlike displaying strings, double quote characters are wrapped around the sql query.

Incoming PHP Data

To see if a variable exists, use the following structure:

if (isset($_POST['variable']))

Don't just assume it exists:

if ($_POST['variable'])

Always assume incoming data is insecure by escaping the input:

databas::query(
  "update mytable
  set column = '". database::input($_POST['variable']) ."'
  where foo = 'bar'
  limit 1;"
);

echo htmlspecialchars($_POST['variable']);

Function Results in PHP

General functions should always return data, not output data to buffer.

For example:

function my_function($string) {
  return $string;
}

and not:

function my_function($string) {
  echo $string;
}

Conditional Expressions

Do not use yoda expressions.

Incorrect:

if (true === condition) {

Correct:

if (condition === true) {

Repetitive Statements in PHP

While loops should be written as:

while (condition == true) {
  ....
}

Walking through an array should be written as:

foreach ($array as $key => $value) {
  ....
}

for-loops should be written as foreach:

foreach (array_keys($array) as $key) {
  echo $array[$key];
}

...rather than:

for ($i=0, $n=count($array); $i<$n; $i++) {
  echo $array[$i];
}

Matryoshka Dolls

Avoid conditional conditions inside iterators:

foreach ($array => $node) {
  if ($node['first'] == 'a') {
    if ($node['second'] == 'b') {
      if ($node['third'] == 'c') {
        do_something();
      }
    }
  }
}

Do instead:

foreach ($array => $node) {
  if ($node['first'] != 'a') continue;
  if ($node['second'] != 'b') continue;
  if ($node['third'] != 'c') continue;
  do_something();
}

Code Compliance

• PHP code must comply with PHP 5.3+ using E_STRICT.

• HTML code must be compliant with HTML 5.

• Style definitions must be compliant with CSS 3.

• Any use of javascript must dedicate the jQuery framework.