Graphic Maniacs

Windows 8 User Agent string

Alex — Mon, 28 May 2012 19:21:15 +0000

Here we go again, with some examples:

Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Trident/6.0)
Mozilla/5.0 (Windows NT 6.2; rv:10.0) Gecko/20100101 Firefox/10.0
Mozilla/5.0 (Windows NT 6.2) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.12 Safari/535.11
Mozilla/5.0 (Windows NT 6.2) AppleWebKit/534.51.22 (KHTML, like Gecko) Version/5.1 Safari/534.50 
Mozilla/5.0 (Windows NT 6.2) AppleWebKit/534.51.22 (KHTML, like Gecko) Version/5.1 Safari/534.50

So it’s pretty simple, let’s wrap up a small function:

function detectWindows8() {
	var os = {};
	var ua = navigator.userAgent;
	if (ua.match(/Windows NT 6.2/i))
		os.windows8 = true;
	return os;
}
 
/// .. later
 
var os = detectWindows8();
if (os.windows8) {
	// do stuff
}

Later on, you can expand the function to detect other OS versions too. Everything’s up to you

PHP “__PHP_Incomplete_Class” error

Alex — Fri, 18 May 2012 08:21:06 +0000

Had this error when loading an object from the $_SESSION?
Here’s why, from official PHP docs:

It’s possible to set a callback-function which will be called, if an undefined class should be instantiated during unserializing. (to prevent getting an incomplete object “__PHP_Incomplete_Class”.) Use your php.ini, ini_set() or .htaccess to define ‘unserialize_callback_func’. Everytime an undefined class should be instantiated, it’ll be called. To disable this feature just empty this setting.

A simple fix would be to load the session_start AFTER the object class declaration, but if it is not possible, then you could simply double-serialize the object. Like this:

// some code running in your application
// then,
$_SESSION['myobject'] = serialize($object);

// then when we need it
$object = unserialize($_SESSION['myobject']);

The reason of the error is because the objects stored in sessions are converted to serialized string, and when we call session_start(), it tries to initialize the object with the class definition which isn’t available yet.

Converting XLSX date-containing field to a real date

Alex — Wed, 14 Mar 2012 08:29:59 +0000

Lately, i was importing an XLSX file using a simple xml-based parser and noticed a strange thing.. The date fields were actually containing integers like 40305, which is actually 2010-05-07 (what??). A bit of investigation, and there’s what that means: the date fields have integers that are the amount of days from 1900-00-00. That means that to convert it to a date we should make

$value = date('Y-m-d', mktime(0,0,0,1,$value-1,1900));

The reason why i subtract 1 from the $value because php counts from 1900-01-01, while XLSX has a date from 1900-00-00. So after that conversion we have a valid date.

Getting a list of WordPress hook actions

Alex — Wed, 18 Jan 2012 13:08:40 +0000

Sometimes content is outputted somewhere where I don’t need (when I run do_action), and I can’t really see what action does that. So to get the list of WordPress actions attached to a hook, use this kind of code:

global $wp_filter;
var_dump($wp_filter['comment_form']);

You will get then something like this:

array(1) {
  [10]=>
  array(2) {
    ["wp_comment_form_unfiltered_html_nonce"]=>
    array(2) {
      ["function"]=>
      string(37) "wp_comment_form_unfiltered_html_nonce"
      ["accepted_args"]=>
      int(1)
    }
    ["akismet_add_comment_nonce"]=>
    array(2) {
      ["function"]=>
      string(25) "akismet_add_comment_nonce"
      ["accepted_args"]=>
      int(1)
    }
  }
}

Pretty cool, now we know what produces all that output.

How to disable Flash, JavaScript and Cookies in Google Chrome

Alex — Tue, 17 Jan 2012 13:51:37 +0000

For those who just need the shortcuts, here’s the link to JavaScript and Cookies options:

chrome://settings/content

For Flash, Silverlight, Quicktime and other similar addons, the link is:

chrome://plugins