PHP custom function to convert American time to Beijing time

function datezhuanhuan($dateparams)
{
$ccc=strtotime($dateparams);
$date=date('Y-m-d');
$bjtime=date('Y-m-d',$ccc );
if($date==$bjtime)
{
$sbjtime=date('Y-m-d H:i:s',$ccc);
echo substr($sbjtime,11,5);
} // bbs .it-home.org
else
{
$sbjtime=date('Y-m-d H:i:s',$ccc);
return substr($sbjtime,5,5);
}
}

Attached, another +8 hour algorithm:

$bj_time = date ("Y-m-d H:i:s" , mktime(gmdate('H')+8,gmdate('i'),gmdate('s'),gmdate('m' ),gmdate('d'),gmdate('Y')));