PHP 5 >= 5.3.0, PHP 7, PHP 8, PECL intl >= 1.0.2, PECL idn >= 0.1
idn_to_ascii - Convert domain name to IDNA ASCII form

     [int$flags = IDNA_DEFAULT],
     [int$variant = INTL_IDNA_VARIANT_UTS46],
     [arrayidna_info = null]
): string|false

This function converts a Unicode domain name to an IDNA ASCII-compatible format.



The domain to convert, which must be UTF-8 encoded.


Conversion options - combination of IDNA_* constants (except IDNA_ERROR_* constants).


Either INTL_IDNA_VARIANT_2003 (deprecated as of PHP 7.2.0) for IDNA 2003 or INTL_IDNA_VARIANT_UTS46 (only available as of ICU 4.6) for UTS #46.


This parameter can be used only if INTL_IDNA_VARIANT_UTS46 was used for variant. In that case, it will be filled with an array with the keys 'result', the possibly illegal result of the transformation, 'isTransitionalDifferent', a boolean indicating whether the usage of the transitional mechanisms of UTS #46 either has or would have changed the result and 'errors', which is an int representing a bitset of the error constants IDNA_ERROR_*.

Return Values

The domain name encoded in ASCII-compatible form, or false on failure


Version Description
7.4.0 The default value of variant is now INTL_IDNA_VARIANT_UTS46 instead of the deprecated INTL_IDNA_VARIANT_2003.
7.2.0 INTL_IDNA_VARIANT_2003 has been deprecated; use INTL_IDNA_VARIANT_UTS46 instead.

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