Question

I am currently working with an array and I need to know how to move an object within that array to the first position, position [0].

I have this

<?php    
$extensions = array(
        '.com'      => array('whois.verisign-grs.com','No match for'),
        '.info'     => array('whois.afilias.net','NOT FOUND'),  
        '.net'      => array('whois.crsnic.net','No match for'),
        '.co.uk'    => array('whois.nic.uk','No match'),        
        '.nl'       => array('whois.domain-registry.nl','is free'),
    );
?>

Now, when the user chooses a domain from the dropdown, I want the selected TLD to be the first in this array.

For ex.

User chooses the .net domain, the array wil be:

$extensions = array(
        '.net'      => array('whois.crsnic.net','No match for'),
        '.com'      => array('whois.verisign-grs.com','No match for'),
        '.info'     => array('whois.afilias.net','NOT FOUND'),  
        '.co.uk'    => array('whois.nic.uk','No match'),        
        '.nl'       => array('whois.domain-registry.nl','is free'),
    );

Answer 1

Merge the nested array into the larger array:

$ext = array(
    '.com'   => array('whois.verisign-grs.com','No match for'),
    '.info'  => array('whois.afilias.net','NOT FOUND'),  
    '.net'   => array('whois.crsnic.net','No match for'),
    '.co.uk' => array('whois.nic.uk','No match'),        
    '.nl'    => array('whois.domain-registry.nl','is free'),
);

$ext = array_merge( Array( ".net" => $ext[".net"] ), $ext );

Demo: http://codepad.org/Mi2S9xTg