http://php.net/manual/en/function.strtr.php

<?php$trans = array("h" => "-", "hello" => "hi", "hi" => "hello");echo strtr("hi all, I said hello", $trans);?>

The above example will output:

hello all, I said hi

function q2b($mstring)
{
$mstring = @preg_replace(‘/([\x80-\xFF])([\x80-\xFF])/xe‘, ‘(ord(substr(\1,0,1))==163&&(ord(substr(\2,1,2))>=161||ord(substr(\2,1,2))<=254)?chr(ord(\2)-0x80):\1\2)‘, $mstring);
$mstring = @preg_replace(‘/\xa3([\xa1-\xfe])/e‘, ‘chr(ord(\1)-0x80)‘, $mstring);

$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‘,‘（‘ => ‘(‘, ‘）‘ => ‘)‘, ‘〔‘ => ‘[‘, ‘〕‘ => ‘]‘, ‘【‘ => ‘[‘,‘】‘ => ‘]‘, ‘〖‘ => ‘[‘, ‘〗‘ => ‘]‘, ‘“‘ => ‘[‘, ‘”‘ => ‘]‘,‘‘‘ => ‘[‘, "‘" => ‘]‘, ‘｛‘ => ‘{‘, ‘｝‘ => ‘}‘, ‘《‘ => ‘<‘,‘》‘ => ‘>‘,‘％‘ => ‘%‘, ‘＋‘ => ‘+‘, ‘—‘ => ‘-‘, ‘－‘ => ‘-‘, ‘～‘ => ‘-‘,‘：‘ => ‘:‘, ‘。‘ => ‘.‘, ‘、‘ => ‘,‘, ‘，‘ => ‘.‘, ‘、‘ => ‘.‘, ‘；‘ => ‘,‘, ‘？‘ => ‘?‘, ‘！‘ => ‘!‘, ‘…‘ => ‘-‘, ‘‖‘ => ‘|‘, ‘”‘ => ‘"‘, "‘" => ‘`‘, ‘‘‘ => ‘`‘, ‘｜‘ => ‘|‘, ‘〃‘ => ‘"‘,‘　‘ => ‘ ‘);


$mstring = strtr($mstring, $arrstrtr);

return $mstring;
}　　

strtr函数的用法