The syntax is straightforward. Any attribute prefixed with data- will be treated as data storage.

<div class="test" data-foo="bar"></div>

jQuery accesses this data like so…

var data = $( 'div.test' ).data( 'foo' ); // returns bar

Support for the data attribute has been added since jQuery version 1.4.3. jQuery’s implementation is smart enough that it can parse the attribute easily and even determine the correct data type used.

What I have found really useful is the fact that the jQuery can parse JSON syntax and return a JSON object. This makes passing data in PHP trivial, using the json_encode method. We also need to use htmlspecialchars method to escape or convert any quotes in the JSON string.

<?php  
$test = array( 'row' => 1, 'col' => 6, 'color' => 'pink' ); //create array of data you want to pass to jquery
$test = json_encode( $test ); //convert array to a JSON string
$test = htmlspecialchars( $test, ENT_QUOTES ); //convert any quotes into HTML entities so JSON string behaves as a proper HTML attribute.
?>
<div class="test" data-complex="<?php echo $test ; ?>"></div>

The jQuery parses the JSON string like so…

var test = $( 'div.test' ).data( 'complex' ); // returns JSON Object

console.log( test.color ); // outputs pink!

Important to note that this method is also backward compatible with older browsers, so there is no excuse not to give it a go!

If you have the IP addresses, then it is trivial.

//First check IP address is valid
$request_ip = $_SERVER['REMOTE_ADDR'];

if ( !preg_match( "/^(([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){3}([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$/", $request_ip ) )
    return false;

$blacklist = array(
'111.222.12.11',
'222.111.21.22',
'221.112.11.12'
);

//check that ip is not blacklisted
if ( in_array( $request_ip, $blacklist ) )
    return false;

If you want to include a range of IP addresses, best to use a regular expression.

$blacklist_ip_range = array(
    '/^122\.244\.(\d+)\.(\d+)/', //for IP address in the range 122.244.0.0 - 122.244.255.255
    '/^123\.(\d+)\.(\d+)\.(\d+)/', //for IP address in the range 123.0.0.0 - 123.255.255.255
);

foreach( $blacklist_ip_range as $ip ) {
    if( preg_match( $ip, $request_ip ) )
       	return false;
    }

If you have a better solution, then please let me know.

var element = document.getElementById( 'some_element_id' );

element.style.cssFloat = 'left';

if ( $("#mydiv").length ){
  // do something here
}

Briefer again…

if ( $("#mydiv")[0] ){
  // do something here
}

via http://aaronrussell.co.uk/legacy/check-if-an-element-exists-using-jquery/

A while ago, I came across a post on such a subject. It was written a few years ago but it’s still as relevant and useful as ever.

http://blog.stevenlevithan.com/archives/faster-trim-javascript 

The author basically compares a bunch of different methods to trim a string across the 2 big browsers at the time, Internet Explorer and Firefox, and figures out the fastest way of doing it.

For more detail, follow the link above, otherwise, here is the conclusion.

Fastest trim method for normal length strings

return str.replace(/^\s\s*/, '').replace(/\s\s*$/, '');

Fastest trim method for super long strings

function trim11 (str) {
	str = str.replace(/^\s+/, '');
	for (var i = str.length - 1; i >= 0; i--) {
		if (/\S/.test(str.charAt(i))) {
			str = str.substring(0, i + 1);
			break;
		}
	}
	return str;
}

Note: For the super geeks out there, this site will show you and allow you to test what is the fastest trim method on a particular browser… enjoy!

This tool will help code meet the indentation rules in the WordPress coding standards.

If you have a group of basic assignments like…

$variable1 = 0;
$long_variable2 = 123213123;
$short = 'test';
$s = 'test2';

This tool will space them so…

$variable1      = 0;
$long_variable2 = 123213123;
$short          = 'test';
$s              = 'test2';

It will also work associative arrays…

array(
'magpie' => 0,
'blog' => 1,
'random' => 2,
'too_long_string' => 3
);

… with spacing …

array(
'magpie'          => 0,
'blog'            => 1,
'random'          => 2,
'too_long_string' => 3
);

The tool is available as a Coda plugin and a TextWrangler UNIX filter.

For Coda

• Download the Coda plugin
• Extract the zip file and double-click the tidy-assignment.codaplugin file
• Select code, right-click, goto Plug-ins->Tidy Assignment

To remove/uninstall the plugin;

• Close Coda
• Goto [your_home_folder]/Library/Application Support/Coda/Plug-ins/
• Delete the file tidy-assignment.codaplugin

For TextWrangler

• Open TextWrangler and open a new text file.
• Copy and paste the code below into this file.

#!/usr/bin/php
<?php

if ( !isset( $_SERVER['argv'] ) && !isset( $_SERVER['argv'][1] ) )
	die();

$fc    = file_get_contents( $_SERVER['argv'][1] );
$lines = explode( "\n", $fc );
$clean = array();
$assoc = false;

$longest_line_index  = 0;
$longest_line_length = 0;

foreach ( $lines as $key => $line ) {
	//remove whitspace
	$line = preg_replace( '/\s\s+/', ' ', trim( $line ) );
	$parts = array();
	
	if ( mb_stripos( $line, '=>' ) !== FALSE ) {
		$parts = explode( "=>", $line );
		$assoc = true;
	}
	elseif ( mb_stripos( $line, '=' ) !== FALSE ) {
		$parts = explode( "=", $line );
	}

	if ( !empty( $parts ) && mb_strlen( $parts[0] ) > $longest_line_length ) {
		$longest_line_index = $key;
		$longest_line_length = mb_strlen( $parts[0] );
	}
	
	if ( mb_strlen( $line ) > 0 )
		$clean[$key] = $line;
}

$longest_line = $clean[$longest_line_index];
$operator = $assoc ? '=>' : '=' ;

//add spaces to line
if ( mb_stripos( $longest_line, $operator ) !== FALSE ) {
	$parts = explode( $operator, $longest_line );
	$longest_line = sprintf( "%s %s %s", trim( $parts[0] ), $operator, trim( $parts[1] ) );
}
else {
	$longest_line = sprintf( "%s", trim( $longest_line ) );
}

//now get the position of equals
$pos = mb_stripos( $longest_line, $operator );
if ( $pos === FALSE )
	$pos = mb_strlen( $longest_line );

foreach ( $clean as $key => &$line ) {
	if ( $key == $longest_line_index )
		$line = $longest_line;
	elseif ( mb_stripos( $line, $operator ) !== FALSE ) {
		$spaces = ' ';
		$parts = explode( $operator, $line );
		if ( !empty( $parts ) )
			while ( mb_stripos( $line, $operator ) < $pos ) {
				$line = sprintf( "%s%s%s %s", trim( $parts[0] ), $spaces, $operator, trim( $parts[1] ) );
				$spaces .= " ";
			}
	}
	else {
		$line = sprintf( "%s", trim( $line ) );
	}
}

echo implode( "\n", $clean );

• Save the file, something like Tidy Assignment.php, in the Filters folder.
• You can find the filters folder by going to the #! menu and go to the Unix Filters sub-menu, and select the Open Filters Folder, like below.
  

• Now anytime you want to tidy assignments, just go to this menu and select the Tidy Assignment script.

First time I created a coda plugin and I am surprised how simple it is. I may experiment with this in the future if I can think of anything useful.

/**
*  Takes XML string and returns a boolean result where valid XML returns true
*/
function is_valid_xml ( $xml ) {
    libxml_use_internal_errors( true );
    
    $doc = new DOMDocument('1.0', 'utf-8');
    
    $doc->loadXML( $xml );
    
    $errors = libxml_get_errors();
    
    return empty( $errors );
}

/**
* Takes an array and returns an array of duplicate items
*/
function get_duplicates( $array ) {
	return array_unique( array_diff_assoc( $array, array_unique( $array ) ) );
}

$string = "Tom\tThumb\t                is sooooooo\t\t\tdumb";
$string = preg_replace( '/\s+/', ' ', $string );
echo $string;
//will echo "Tom Thumb is sooooooo dumb"

/**
 * Convert a comma separated file into an associated array.
 * The first row should contain the array keys.
 * 
 * Example:
 * 
 * @param string $filename Path to the CSV file
 * @param string $delimiter The separator used in the file
 * @return array
 * @link http://gist.github.com/385876
 * @author Jay Williams <http://myd3.com/>
 * @copyright Copyright (c) 2010, Jay Williams
 * @license http://www.opensource.org/licenses/mit-license.php MIT License
 */
function csv_to_array($filename='', $delimiter=',')
{
	if(!file_exists($filename) || !is_readable($filename))
		return FALSE;

	$header = NULL;
	$data = array();
	if (($handle = fopen($filename, 'r')) !== FALSE)
	{
		while (($row = fgetcsv($handle, 1000, $delimiter)) !== FALSE)
		{
			if(!$header)
				$header = $row;
			else
				$data[] = array_combine($header, $row);
		}
		fclose($handle);
	}
	return $data;
}

Found here, courtesy of jaywilliams