Formula for (PHP 3 >= 3.0.6, PHP 4, PHP 5)
string convert_cyr_string ( string str, string from, string to )

Parameter
string str = Required. The string to convert
string from = Required. A character that specifies what Cyrillic character-set to convert from
string to = Required. A character that specifies what Cyrillic character-set to convert to

Description
This function returns the given string converted from one Cyrillic character set to another. The from and to arguments are single characters that represent the source and target Cyrillic character sets. The supported types are:
k - koi8-r
w - windows-1251
i - iso8859-5
a - x-cp866
d - x-cp866
m - x-mac-cyrillic

Note: This function is binary-safe.

Example