idn_to_ascii
(PHP 5 >= 5.3.0, PECL intl >= 1.0.2, PECL idn >= 0.1)
idn_to_ascii — Convert domain name to IDNA ASCII form.
Description
Procedural style
   string idn_to_ascii
    ( string $domain
   [, int $options
  ] )
  This function converts Unicode domain name to IDNA ASCII-compatible format.
Parameters
- domain
- 
      Domain to convert. In PHP 5 must be UTF-8 encoded. 
- options
- 
      Conversion options - combination of IDNA_* constants. 
Return Values
Domain name encoded in ASCII-compatible form. or FALSE on failure
Examples
Example #1 idn_to_ascii() example
<?php
echo idn_to_ascii('täst.de'); 
?>
The above example will output:
xn--tst-qla.de