函数
function weekStartEnd($year,$week=1)
{
$w = date('W');
$diff = $w-$week;
$weekday['start']=mktime(0,0,0,date('m'),date('d')-date('w')+1-$diff*7,date('Y'));
$weekday['end']=mktime(23,59,59,date('m'),date('d')-date('w')+7-$diff*7,date('Y'));
return $weekday;
}