php gb2312转utf8函数是什么

http://www.baidu.com/s?wd=%D6%D0%CE%C4

http://www.google.cn/search?hl=zh-CN&source=hp&q=%E4%B8%AD%E6%96%87&aq=f&oq=

header('Content-type: text/html; charset=utf-8');
echo '
百度关键词URL编码转换示例：
';
$urlBaidu = 'http://www.baidu.com/s?wd=%D6%D0%CE%C4';
$arrParse = parse_url($urlBaidu);
parse_str($arrParse ['query'],$output);
echo '乱码：' . $output['wd'] . '
';
//将gb2312编码转换成utf-8编码
$strUTF8 = mb_convert_encoding($output['wd'], 'utf-8', 'gb2312');
echo '可读码：' . $strUTF8 . '
';
echo '
谷歌关键词URL编码转换示例：
';
$urlGoogle = 'http://www.google.cn/search?hl=zh-CN&source=hp&q=%E4%B8%AD%E6%96%87&aq=f&oq=';
$arrParse = parse_url($urlGoogle);
parse_str($arrParse ['query'],$output);
//谷歌关键词URL编码是utf-8，不用再作转换
echo '可读码：' . $output['q'] . '
';