Tag Archives: Computing

The Difference Between .live() and .delegate and Which One Should be Used

javascript, web development, , , , ,

There are so many posts about that topic out there, but I’d like to be rather breve! The delegate() method comes with the last major version of the jQuery – 1.4 and it gives a context to the event. So please use delegate() instead of live(), just because not everything’s attached to the document element, but to the selected object.

PHP Functions: realpath()

micro tutorial, PHP, , , , , , , ,

Watch Out – Hard Code

Perhaps every developer knows that hard coded paths are no good! The code’s good to be flexible and extensible, but what the way to achieve that? In a typically developed application you’re completely sure the way the folders are nested will be permanent and no change will occur, and that’s maybe true, but however don’t be completely sure.

An Example

Let’s take a typical example. You’ve to access a uploaded file with PHP. By default the files are uploaded in the /tmp folder with PHP given name. That’s why immediately after the upload (the form submit) you’ve to process the _POST and the _FILES arrays and perhaps move the uploaded file somewhere else.

However you’d like to access this file wherever the application is – on the production servers or on the development server or even on the localhost!

I ran into that kind of problem/task. The thing I’d like to achieve was a bit different. I constructed the path with the dirname() function, but there were still ‘/../../’ chunks in it. So the solution is the realpath() function that removes those chunks and converts the path into one “calculated” real path to the file.

Let me show you an example:

// get the uploaded file path
$scriptPath = dirname(__FILE__);
 
// get the realpath to avoid the /../ part of the path
// with dirname they remain in the path
$uploadFolderPath = realpath($scriptPath . '/../../folder_name/');

If you were using dirname() you’d get something like that:

/folder1/folder2/folder3/../../folder2/file.txt

Now with realpath() the result is:

/folder1/folder2/file.txt

That’s more clear and even both are working correctly I’d prefer the second one!

Check YouTube Video Existence with Zend_Gdata_YouTube

micro tutorial, PHP, zend framework, , , , , , , , , , , , , , ,

The Video Has Been Removed?!

Have you ever seen the famous message on YouTube: “This video has been removed by the user.”, but what if you’re trying to grab that video via the Zend_Gdata_YouTube?

That can happen when you’re reading the feed for a channel or a user’s list of videos. In the feed everything’s OK – once the video is uploaded it appears into the feed. After that the user removes the video and visiting the link from the feed you’ll get the message above.

Actually what happens when you try to read this “video entry” within a Zend Framework’s application. There must be some way to catch this message?

Trying to Catch

The answer is pretty simple! Zend_Gdata_YouTube’s throwing an exception and it can be easily cached. Here’s some source code:

$apiKey = 'your_api_key';
$client = new Zend_Http_Client();
$gdata = new Zend_Gdata_YouTube($client, 'my-app', null, $apiKey);
try {
       $gdata->getVideoEntry($video_id);
} catch(Zend_Gdata_App_Exception $e) {
       echo $e->getMessage();
}

PHP Associative Arrays Coding Style

micro tutorial, PHP, , , , , , , , , , , , , ,

No PHP programmer writes code without arrays. Sound strange, but as many programmers there are, as many ways to format the array notation there are.

My advice is to rely on a defined standard. I personally use the Zend Framework’s coding style.

So how to format the code? The first way is on the same line:

$myArray = array('key1' => 'value1',
		 'key2' => 'value2');

And the other, perhaps more clear way is to place the associative pairs on a new line:

$myArray = array(
	'key1' => 'value1',
	'key2' => 'value2',
);

Note that in the second example there’s a comma after the second pair. This is correct PHP syntax and is strongly encouraged!

It’s up to you which way to take. However it mainly depends on the case, but please use standards.

PHP: The Array Element Doesn’t Exist – Suppress the Warnings

micro tutorial, PHP, , , , , , , , ,

What’s the problem?

If you code PHP from couple of hours you are probably familiar with the following problem:

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<?php
 
	error_reporting(E_ALL);
 
	$arr = array();
 
	echo $arr[3];
 
?>

The first and most common solution is just by adding the isset() statement and the code will look like that:

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<?php
 
	error_reporting(E_ALL);
 
	$arr = array();
 
        if (isset($arr[3]))
	        echo $arr[3];
 
?>

However do you know there’s is another simple and elegant solution? Simply add the @ sign to suppress the element existence

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<?php
 
	error_reporting(E_ALL);
 
	$arr = array();
 
	echo @$arr[3];
 
?>