将js的以%u开头的unicode编码(标准应为＆＃开头)，转换为utf-8编码．
<?php
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 $decodedStr;
}
function code2utf($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 '';
}
$str = "%3d";
echo unescape($str);
?>