php日期方面

date_default_timezone_set('PRC');
/**
* 求取从某日起经过一定天数后的日期,
* 排除周六周日和节假日
* @param $start 开始日期
* @param $offset 经过天数
* @param $exception 例外的节假日
* @param $allow 允许的日期(预留参数)
* @return
* examples:输入(2010-06-25,5,''),得到2010-07-02
*/
function getEndDay( $start='now', $offset=0, $exception='', $allow='' ){
//先计算不排除周六周日及节假日的结果
$starttime = strtotime($start);
$endtime = $starttime + $offset * 24 * 3600;
$end = date('Y-m-d', $endtime);
//然后计算周六周日引起的偏移
$weekday = date('N', $starttime);//得到星期值：1-7
$remain = $offset % 7;
$newoffset = 2 * ($offset - $remain) / 7;//每一周需重新计算两天
if( $remain > 0 ){//周余凑整
$tmp = $weekday + $remain;
if( $tmp >= 7 ){
$newoffset += 2;
}else if( $tmp == 6 ){
$newoffset += 1;
}
//考虑当前为周六周日的情况
if( $weekday == 6 ){
$newoffset -= 1;
}else if( $weekday == 7 ){
$newoffset -= 2;
}
}
//再计算节假日引起的偏移
if( is_array($exception) ){//多个节假日
foreach ($exception as $day){
$tmp_time = strtotime($day);
if( $tmp_time>$starttime && $tmp_time<=$endtime ){//在范围(a,b]内
$weekday_t = date('N', $tmp_time);
if($weekday_t <= 5){//防止节假日与周末重复
$newoffset += 1;
}
}
}
}else{//单个节假日
if( $exception!='' ){
$tmp_time = strtotime($exception);
if( $tmp_time>$starttime && $tmp_time<=$endtime ){
$weekday_t = date('N', $tmp_time);
if($weekday_t <= 5){
$newoffset += 1;
}
}
}

}
//根据偏移天数，递归做等价运算
if($newoffset > 0){
#echo "[{$start} -> {$offset}] = [{$end} -> {$newoffset}]"."<br />\n";
return getEndDay($end,$newoffset,$exception,$allow);
}else{
return $end;
}
}
/**
* 暴力循环方法
*/
function getEndDay2( $start='now', $offset=0, $exception='', $allow='' ){
$starttime = strtotime($start);
$tmptime = $starttime + 24*3600;

while( $offset > 0 ){
$weekday = date('N', $tmptime);
$tmpday = date('Y-m-d', $tmptime);
$bfd = false;//是否节假日
if(is_array($exception)){
$bfd = in_array($tmpday,$exception);
}else{
$bfd = ($exception==$tmpday);
}
if( $weekday<=5 && !$bfd){//不是周末和节假日
$offset--;
#echo "tmpday={$tmpday}"."<br />";
}
$tmptime += 24*3600;
}

return $tmpday;
}
$exception = array(
'2010-01-01','2010-01-02','2010-01-03',
'2010-04-03','2010-04-04','2010-04-05',
'2010-05-01','2010-05-02','2010-05-03',
'2010-06-14','2010-06-15','2010-06-16',
'2010-09-22','2010-09-23','2010-09-24',
'2010-10-01','2010-10-02','2010-10-03','2010-10-04',
'2010-10-05','2010-10-06','2010-10-07',

);
//echo getEndDay('2010-08-27',3,'');
//echo getEndDay('2010-06-25',15,'2010-07-07');
$t1 = microtime();
echo getEndDay('2010-05-12',66,$exception)."<br />";
$t2 = microtime();echo "use ".($t2-$t1)." s <br />";
echo getEndDay2('2010-05-12',66,$exception)."<br />";
$t3 = microtime();echo "use ".($t3-$t2)." s <br />";