Convert full-width characters to half-width characters PHP function

/**
 * 全角字符转换为半角字符
 */
function make_semiangle ( $str )
{
$arr = array ( '０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4',
	               '５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9',
	               'Ａ' => 'A', 'Ｂ' => 'B', 'Ｃ' => 'C', 'Ｄ' => 'D', 'Ｅ' => 'E',
	               'Ｆ' => 'F', 'Ｇ' => 'G', 'Ｈ' => 'H', 'Ｉ' => 'I', 'Ｊ' => 'J',
	               'Ｋ' => 'K', 'Ｌ' => 'L', 'Ｍ' => 'M', 'Ｎ' => 'N', 'Ｏ' => 'O',
	               'Ｐ' => 'P', 'Ｑ' => 'Q', 'Ｒ' => 'R', 'Ｓ' => 'S', 'Ｔ' => 'T',
	               'Ｕ' => 'U', 'Ｖ' => 'V', 'Ｗ' => 'W', 'Ｘ' => 'X', 'Ｙ' => 'Y',
	               'Ｚ' => 'Z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd',
	               'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i',
	               'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n',
	               'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's',
	               'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x',
	               'ｙ' => 'y', 'ｚ' => 'z',
	               '（' => '(', '）' => ')', '〔' => '[', '〕' => ']', '【' => '[',
	               '】' => ']', '〖' => '[', '〗' => ']', '“' => '[', '”' => ']',
	               '‘' => '[', '’' => ']', '｛' => '{', '｝' => '}', '《' => '<', '》' => '>',
	               '％' => '%', '＋' => '+', '—' => '-', '－' => '-', '～' => '-',
	               '：' => ':', '。' => '.', '、' => ',', '，' => '.', '、' => '.',
	               '；' => ',', '？' => '?', '！' => '!', '…' => '-', '‖' => '|',
	               '”' => '"', '’' => '`', '‘' => '`', '｜' => '|', '〃' => '"',
	               '　' => ' ' );

return strtr ( $str, $arr );
}

转换为, PHP