php 判斷月份中最小的日期

比如：一個數組裡邊裝的日期：2014-01-01,2014-01-02,2014-01-22，2014-02-22,2014-02-26,2014-03-03,2014-03-25,2014-03-28

要達到：把月份中最小的日期取出來，如下所示：

2014-01-01

2014-02-22

2014-03-03

並且計算月份所屬日期數：（比如1月份有3個（2014-01-01,2014-01-02,2014-01-22））

01月份-》3

02月份-》2

03月份-》3

這兩個功能單獨寫。請大俠賜教，謝謝！！！！！！！！！

回複討論(解決方案)

$ar = array(  '2014-01-01',  '2014-01-02',  '2014-01-22',  '2014-02-22',  '2014-02-26',  '2014-03-03',  '2014-03-25',  '2014-03-28',);$r1 = $r2 = array();foreach($ar as $d) {  list($y, $m, $d) = explode('-', $d);  if(! isset($r1[$y.$m])) $r1[$y.$m] = 32;  $r1[$y.$m] = min($r1[$y.$m], $d);  if(! isset($r2[$y.$m])) $r2[$y.$m] = 0;  $r2[$y.$m]++;}print_r($r1);print_r($r2);

Array
(
[201401] => 01
[201402] => 22
[201403] => 03
)
Array
(
[201401] => 3
[201402] => 2
[201403] => 3
)

1.

$arr = array('2014-01-01','2014-01-02','2014-01-22','2014-02-22','2014-02-26','2014-03-03','2014-03-25','2014-03-28');sort($arr);$out = array();foreach ($arr as $key => $value) {$mouth = date('n',strtotime($value));if(!in_array($mouth, array_keys($out))) $out[$mouth] = $value;}var_dump($out);

2.

$arr = array('2014-01-01','2014-01-02','2014-01-22','2014-02-22','2014-02-26','2014-03-03','2014-03-25','2014-03-28');$newArr = array_map('cout', $arr);function cout($n){return date('n',strtotime($n));}print_r ( array_count_values ( $newArr ));

比較簡單

$arr = array('2014-01-01','2014-01-02','2014-01-22','2014-02-22','2014-02-26','2014-03-03','2014-03-25','2014-03-28');$data = array();foreach($arr as $_arr){    list($y, $m, $d) = explode('-', $d);    $data[$m] = isset($data[$m])  ? ($data[$m]>$d ? $d : $data[$m]) : $d;}

如果要考慮不同年相同月份的情況，例如2014-02 與 2013-02 需要分開統計。key的值要用Y-m格式。

$val){        echo date('Y-m-d',$val).'
';    }}function month_days($months){    $tmp = array();    foreach($months as $month){        $key = date('Y-m',strtotime($month));        isset($tmp[$key])? $tmp[$key]++ : $tmp[$key]=1;    }    foreach($tmp as $key=>$val){        echo $key.'->'.$val.'
';    }}?>

