<?php class Datefmt{    function __construct() {}   /**    * 根据指定日期获取所在周的起始时间和结束时间    */   public function get_weekinfo_by_date($date) {     $idx = strftime("%u", strtotime($date));     $mon_idx = $idx - 1;     $sun_idx = $idx - 7;     return array(       'week_start_day' => strftime('%Y-%m-%d', strtotime($date) - $mon_idx * 86400),       'week_end_day' => strftime('%Y-%m-%d', strtotime($date) - $sun_idx * 86400),       );   }   /**    * 根据指定日期获取所在月的起始时间和结束时间    */   public function get_monthinfo_by_date($date){     $ret = array();     $timestamp = strtotime($date);     $mdays = date('t', $timestamp);     return array(       'month_start_day' => date('Y-m-1', $timestamp),       'month_end_day' => date('Y-m-'.$mdays, $timestamp)       );   }   /**    * 获取指定日期之间的各个周    */   public function get_weeks($sdate, $edate) {     $range_arr = array();     // 检查日期有效性     $this->check_date(array($sdate, $edate));     // 计算各个周的起始时间     do {       $weekinfo = $this->get_weekinfo_by_date($sdate);       $end_day = $weekinfo['week_end_day'];        $start = $this->substr_date($weekinfo['week_start_day']);       $end = $this->substr_date($weekinfo['week_end_day']);       $range = "{$start} ~ {$end}";       $range_arr[] = $range;        $sdate = date('Y-m-d', strtotime($sdate)+7*86400);     }while($end_day < $edate);     return $range_arr;   }   /**   * 获取指定日期之间的各个月   */   public function get_months($sdate, $edate) {     $range_arr = array();     do {       $monthinfo = $this->get_monthinfo_by_date($sdate);       $end_day = $monthinfo['month_end_day'];        $start = $this->substr_date($monthinfo['month_start_day']);       $end = $this->substr_date($monthinfo['month_end_day']);       $range = "{$start} ~ {$end}";       $range_arr[] = $range;        $sdate = date('Y-m-d', strtotime($sdate.'+1 month'));     }while($end_day < $edate);     return $range_arr;   }   /**    * 截取日期中的月份和日    * @param string $date    * @return string $date    */   public function substr_date($date) {     if ( ! $date) return FALSE;     return date('m-d', strtotime($date));   }   /**   * 检查日期的有效性 YYYY-mm-dd   * @param array $date_arr   * @return boolean   */   public function check_date($date_arr) {     $invalid_date_arr = array();     foreach ($date_arr as $row) {       $timestamp = strtotime($row);       $standard = date('Y-m-d', $timestamp);       if ($standard != $row) $invalid_date_arr[] = $row;     }     if ( ! empty($invalid_date_arr)) {       die("invalid date -> ".print_r($invalid_date_arr, TRUE));     }   } }

<?php     require_once "Datefmt.class.php";      $datefmt = new Datefmt();     // 输出11月1日和30日之间的各周     var_dump($datefmt->get_weeks('2014-11-05', '2014-11-29'));     /*结果为     array(4) {       [0]=>       string(13) "11-03 ~ 11-09"       [1]=>       string(13) "11-10 ~ 11-16"       [2]=>       string(13) "11-17 ~ 11-23"       [3]=>       string(13) "11-24 ~ 11-30"     }     */     // 输出2月1日和11月30日     var_dump($datefmt->get_months('2014-02-03', '2014-11-29'));     /*结果为     array(10) {       [0]=>       string(13) "02-01 ~ 02-28"       [1]=>       string(13) "03-01 ~ 03-31"       [2]=>       string(13) "04-01 ~ 04-30"       [3]=>       string(13) "05-01 ~ 05-31"       [4]=>       string(13) "06-01 ~ 06-30"       [5]=>       string(13) "07-01 ~ 07-31"       [6]=>       string(13) "08-01 ~ 08-31"       [7]=>       string(13) "09-01 ~ 09-30"       [8]=>       string(13) "10-01 ~ 10-31"       [9]=>       string(13) "11-01 ~ 11-30"     }     */