php - 在 PHP 中重组一系列事件，将参与者与共同位置结合起来

Question

我有一个 PHP 数组，用于保存某人将参加事件的日期、地点和时间。它以这种格式开始(原始数组总是按日期/时间顺序传递):

array(2) {
  [0]=>
  array(2) {
    ["date"]=>
    string(8) "1st June"
    ["events"]=>
    array(4) {
      [0]=>
      array(3) {
        ["location"]=>
        string(7) "Venue A"
        ["name"]=>
        string(4) "Pete"
        ["time"]=>
        string(6) "4.00pm"
      }
      [1]=>
      array(3) {
        ["location"]=>
        string(7) "Venue A"
        ["name"]=>
        string(4) "John"
        ["time"]=>
        string(6) "4.30pm"
      }
      [2]=>
      array(3) {
        ["location"]=>
        string(7) "Venue B"
        ["name"]=>
        string(5) "Chris"
        ["time"]=>
        string(6) "7.30pm"
      }
      [3]=>
      array(3) {
        ["location"]=>
        string(7) "Venue A"
        ["name"]=>
        string(4) "Mark"
        ["time"]=>
        string(6) "8.00pm"
      }
    }
  }
  [1]=>
  array(2) {
    ["date"]=>
    string(8) "2nd June"
    ["events"]=>
    array(4) {
      [0]=>
      array(3) {
        ["location"]=>
        string(7) "Venue B"
        ["name"]=>
        string(4) "Fred"
        ["time"]=>
        string(6) "5.00pm"
      }
      [1]=>
      array(3) {
        ["location"]=>
        string(7) "Venue C"
        ["name"]=>
        string(5) "Boris"
        ["time"]=>
        string(6) "6.00pm"
      }
      [2]=>
      array(3) {
        ["location"]=>
        string(7) "Venue A"
        ["name"]=>
        string(6) "Rupert"
        ["time"]=>
        string(6) "7.00pm"
      }
      [3]=>
      array(3) {
        ["location"]=>
        string(7) "Venue A"
        ["name"]=>
        string(5) "David"
        ["time"]=>
        string(6) "9.00pm"
      }
    }
  }
}

我需要做的是将其组合起来，以便同一位置的与会者被分组在一起，而不同位置的另一名与会者不会拆分列表。所以上面的数组将更改为:

array(2) {
  [0]=>
  array(2) {
    ["date"]=>
    string(8) "1st June"
    ["events"]=>
    array(3) {
      [0]=>
      array(2) {
        ["location"]=>
        string(7) "Venue A"
        ["attendees"]=>
        array(2) {
          [0]=>
          array(2) {
            ["name"]=>
            string(4) "Pete"
            ["time"]=>
            string(6) "4.00pm"
          }
          [1]=>
          array(2) {
            ["name"]=>
            string(4) "John"
            ["time"]=>
            string(6) "4.30pm"
          }
        }
      }
      [1]=>
      array(2) {
        ["location"]=>
        string(7) "Venue B"
        ["attendees"]=>
        array(1) {
          [0]=>
          array(2) {
            ["name"]=>
            string(5) "Chris"
            ["time"]=>
            string(6) "7.30pm"
          }
        }
      }
      [2]=>
      array(2) {
        ["location"]=>
        string(7) "Venue A"
        ["attendees"]=>
        array(1) {
          [0]=>
          array(2) {
            ["name"]=>
            string(4) "Mark"
            ["time"]=>
            string(6) "8.00pm"
          }
        }
      }
    }
  }
  [1]=>
  array(2) {
    ["date"]=>
    string(8) "2nd June"
    ["events"]=>
    array(3) {
      [0]=>
      array(2) {
        ["location"]=>
        string(7) "Venue B"
        ["attendees"]=>
        array(1) {
          [0]=>
          array(2) {
            ["name"]=>
            string(4) "Fred"
            ["time"]=>
            string(6) "5.00pm"
          }
        }
      }
      [1]=>
      array(2) {
        ["location"]=>
        string(7) "Venue C"
        ["attendees"]=>
        array(1) {
          [0]=>
          array(2) {
            ["name"]=>
            string(5) "Boris"
            ["time"]=>
            string(6) "6.00pm"
          }
        }
      }
      [2]=>
      array(2) {
        ["location"]=>
        string(7) "Venue A"
        ["attendees"]=>
        array(2) {
          [0]=>
          array(2) {
            ["name"]=>
            string(6) "Rupert"
            ["time"]=>
            string(6) "7.00pm"
          }
          [1]=>
          array(2) {
            ["name"]=>
            string(5) "David"
            ["time"]=>
            string(6) "9.00pm"
          }
        }
      }
    }
  }
}

所以这就是我想出如何处理变量并逐步遍历原始数组的方法:

// $eventsArray holds the original array data a per the first example
$newArray = array();
foreach($eventsArray as $day) {
    $curLocation = '';
    $todaysEvents = array();
    $teKey = -1;
    foreach($day['events'] as $event) {
        if($curLocation==$event['location']) {
            $todaysEvents[$teKey]['attendees'][] = array(
                'name' => $event['name'],
                'time' => $event['time']
            );
        } else {
            $todaysEvents[] = array(
                'location' => $event['location'],
                'attendees' => array(
                    array(
                        'name' => $event['name'],
                        'time' => $event['time']
                    )
                )
            );
            $teKey = $teKey + 1;
        }
        $curLocation=$event['location'];
    }
    $newArray[] = array(
        'date' => $day['date'],
        'events' => $todaysEvents
    );
}

这有效!那我为什么要在 Stack 上提问呢？因为这感觉非常笨重，而且我不相信没有更有效的方法来做到这一点。我觉得我在这里增加了不必要的开销。

Answer 1

这是使用一些 PHP 7 (7.3+) 功能的替代版本:

$resultEvents = [];

foreach ($events as ['date' => $date, 'events' => $dayEvents]) {
  $resultDayEvents = ['date' => $date, 'events' => []];

  foreach ($dayEvents as ['location' => $location, 'name' => $name, 'time' => $time]) {
    $attendee = ['name' => $name, 'time' => $time];
    if ($location === ($previousLocation ?? null)) {
      $resultDayEvents['events'][array_key_last($resultDayEvents['events'])]['attendees'][] = $attendee;
    } else {
      $resultDayEvents['events'][] = ['location' => $location, 'attendees' => [$attendee]];
    }
    $previousLocation = $location;
  }

  $resultEvents[] = $resultDayEvents;
}

演示:https://3v4l.org/bC4LK