PHP

@php

Datestamps


 <?php
 //mktime(hour,minute,second,month,day,year)

 echo date("Y/m/d", mktime(0,0,0,11,11,2011));
 //2011/11/11
 ?>

Turn off error reporting


 <?php
 error_reporting(0)
 ?>

Check if domain resolves


 <?php
 checkdnsrr($host)
 ?>

Authenticating users


 <?php
 session_start();
 // Check for session injection
 if (isset($_REQUEST['_SESSION'])) {
	 session_destroy();
	 die('');
 } elseif (isset($_SESSION['HTTP_USER_AGENT'])) {
	 if ($_SESSION['HTTP_USER_AGENT'] != md5($_SERVER['HTTP_USER_AGENT'])) {
		 session_destroy();
		 die('');
	 }
 }
 // At end of page, let's regenerate the session ID
 if(isset($_SESSION['username'])) {
	 session_regenerate_id(TRUE);
 } 
 ?>

Run a server instance with a script

Requires PHP >= 5.4 - http://php.net/manual/en/features.commandline.webserver.php

php -S localhost:8000 router.php

Validation

Numeric validation


 <?php
 is_int($var)
 is_numeric($var)
 ?>

Export to CSV


 <?php
 header("Expires: 0");
 header("Cache-control: private");
 header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
 header("Content-Description: File Transfer");
 header("Content-Type: text/csv");
 header("Content-disposition: attachment; filename=rawlogs.csv");
 ?>

Get filename


 <?php
 $FILE_NAME = basename($_SERVER["PHP_SELF"]);
 ?>

Return multiple values


 <?php
 function mult() {
	 return array(0, 1);
 }
 
 list ($zero, $one) = mult();
 ?>

Create an array of objects


 <?php
 $allCars=array();
 $result = mysql_query($SQL);
 
 while ($rowInfo = mysql_fetch_assoc($result))
 { 
 	 $tempCar=new Car();
  
 	 $tempCar->setMake($rowInfo['car_make']);
 	 $tempCar->setModel($rowInfo['car_model']);
 	 $tempCar->setColor($rowInfo['car_color']);
 
 	 $allCars[]=$tempCar;
 }
 ?>

Include PEAR (Dreamhost)


 <?php
 //Include my PEAR path
 set_include_path("." . PATH_SEPARATOR . ($UserDir = dirname($_SERVER['DOCUMENT_ROOT'])) . "/pear/php" . PATH_SEPARATOR . get_include_path());
 ?>

Scrape $_GET parameters

If mod_rewrite or some other mechanism is preventing the filling of the $_GET array, use this:


 <?php
 parse_str($_SERVER['QUERY_STRING'], $_GET);
 ?>

Convert command line arguments into GET variables


 <?php
 parse_str(implode('&amp;', array_slice($argv, 1)), $_GET);
 ?>

Get PHP config info

# Get configuration (like phpinfo())
php -i
# Get location of php.ini
php --ini

Redirect to a different URL


 <?php
 header("Location: http://www.example.com/"); 
 ?>

Syntax cheatsheet


 <?php
 if ($blah == 0) {
   // code
 } elseif ($blah == 1) {
   // code
 } else {
   // code
 }
 
 $arr = array(1, 2, 3, 4);
 foreach ($arr as $value) {
	 print $value;
 }
 
 switch ($blah) {
   case 0:
	 // code
	 break;
   case 1:
	 // code
	 break;
   default:
	 // code
	 break;
 
 function foo () {
   return 0;
 }
 ?>