php preg_match_all 与preg_match 区别与实例

/*

搜索所有匹配正则表达式的模式并提出给予他们在比赛中受的标志指定的顺序。第一场比赛后发现，随后的搜查是继续从最后一场比赛结束。

实例

出输

*/

//实例

/*
两个结果完全相同,所以个人觉得自php自带的函数高效于用户自定义函数
*/
?>

//加上

//方法二针对二级域名

//这样的话，所有111cn.net的二级域名都同时登陆了。

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111cn.net
    if($newoffset > 0){
        #echo "[{$start} -> {$offset}] = [{$end} -> {$newoffset}]"."<br /> ";
        return getendday($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 />";