PHP: Replace umlauts with closest 7-bit ASCII aequivalent in an UTF-8 string

Question

What I want to do is to remove all accents and umlauts from a string, turning "lärm" into "larm" or "andré" into "andre". What I tried to do was to utf8_decode the string and then use strtr on it, but since my source file is saved as UTF-8 file, I can't enter the ISO-8859-15 characters for all umlauts - the editor inserts the UTF-8 characters.

Obviously a solution for this would be to have an include that's an ISO-8859-15 file, but there must be a better way than to have another required include?

echo strtr(utf8_decode($input), 
           'ŠŒŽšœžŸ¥µÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿ',
           'SOZsozYYuAAAAAAACEEEEIIIIDNOOOOOOUUUUYsaaaaaaaceeeeiiiionoooooouuuuyy');

UPDATE: Maybe I was a bit inaccurate with what I try to do: I do not actually want to remove the umlauts, but to replace them with their closest "one character ASCII" aequivalent.

Answer 1

Okay, found an obvious solution myself, but it's not the best concerning performance...

echo strtr(utf8_decode($input), 
           utf8_decode('ŠŒŽšœžŸ¥µÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿ'),
           'SOZsozYYuAAAAAAACEEEEIIIIDNOOOOOOUUUUYsaaaaaaaceeeeiiiionoooooouuuuyy');

Answer 2

iconv("utf-8","ascii//TRANSLIT",$input);

Extended example

Answer 3

Keep in mind that the string you produce will not necessarily have the same meaning as the original string, as discussed in this similar question. It's a serviceable approach for cleaning file names, but probably not something you'd want to do if you are planning to display your new string as text.