User:Frap/Reverse domain name notation

Encyclopedic article can be found on Wikipedia.

Regex:

^[A-Za-z]{2,6}((?!-)[A-Za-z0-9-]{1,63}(?<!-)\\.)+$

C#

<lang csharp>/// <summary> /// Reverses a domain name. /// </summary> /// <param name="domain">A domain name.</param> /// <returns>A string with the domain name reversed.</returns> private static string ReverseDomainNameNotation(string domain) {

   return string.Join(".", domain.Split('.').Reverse());

}</lang>

JavaScript

<lang javascript>function reverseDomain(domain) {

   return domain.split('.').reverse().join('.');

}</lang>

Perl

<lang perl>sub reversedomain {

   return join ".", reverse split /\./, $_[0];

}</lang>

PHP

<lang php>function reverseDomain(domain) {

   return implode('.', array_reverse(explode('.', domain)));

}</lang>

PowerShell

<lang powershell>function Get-ReverseDomain($domain) {

   $segments = $domain.split('.')
   [array]::reverse($segments)
   return $segments -join '.';

}</lang>

Python

<lang python>def reverse_domain(domain):

   """Reverses a domain name."""
   return '.'.join(reversed(domain.split('.')))</lang>

Ruby

<lang ruby># Reverses a domain name. def reverse_domain(domain)

 domain.sp­lit('.').r­everse.j­oin('.')

end</lang>