I was searching for a function similar to Javascript's unescape(). In most cases it is OK to use url_decode() function but not if you've got UTF characters in the strings. They are converted into %uXXXX entities that url_decode() cannot handle.
I googled the net and found a function which actualy converts these entities into HTML entities (&#xxx;) that your browser can show correctly. If you're OK with that, the function can be found here: http://pure-essence.net/stuff/code/utf8RawUrlDecode.phps
But it was not OK with me because I needed a string in my charset to make some comparations and other stuff. So I have modified the above function and in conjuction with code2utf() function mentioned in some other note here, I have managed to achieve my goal:
<?php
/**
* Function converts an Javascript escaped string back into a string with specified charset (default is UTF-8).
* Modified function from http://pure-essence.net/stuff/code/utf8RawUrlDecode.phps
*
* @param string $source escaped with Javascript's escape() function
* @param string $iconv_to destination character set will be used as second paramether in the iconv function. Default is UTF-8.
* @return string
*/
function unescape($source, $iconv_to = 'UTF-8') {
$decodedStr = '';
$pos = 0;
$len = strlen ($source);
while ($pos < $len) {
$charAt = substr ($source, $pos, 1);
if ($charAt == '%') {
$pos++;
$charAt = substr ($source, $pos, 1);
if ($charAt == 'u') {
// we got a unicode character
$pos++;
$unicodeHexVal = substr ($source, $pos, 4);
$unicode = hexdec ($unicodeHexVal);
$decodedStr .= code2utf($unicode);
$pos += 4;
}
else {
// we have an escaped ascii character
$hexVal = substr ($source, $pos, 2);
$decodedStr .= chr (hexdec ($hexVal));
$pos += 2;
}
}
else {
$decodedStr .= $charAt;
$pos++;
}
}
if ($iconv_to != "UTF-8") {
$decodedStr = iconv("UTF-8", $iconv_to, $decodedStr);
}
return $decodedStr;
}
/**
* Function coverts number of utf char into that character.
* Function taken from: http://sk2.php.net/manual/en/function.utf8-encode.php#49336
*
* @param int $num
* @return utf8char
*/
function code2utf($num){
if($num<128)return chr($num);
if($num<2048)return chr(($num>>6)+192).chr(($num&63)+128);
if($num<65536)return chr(($num>>12)+224).chr((($num>>6)&63)+128).chr(($num&63)+128);
if($num<2097152)return chr(($num>>18)+240).chr((($num>>12)&63)+128).chr((($num>>6)&63)+128) .chr(($num&63)+128);
return '';
}
?>