在对象阵列中查找最接近的日期/时间

Question

I'm looking for some advise on what would be the best way to find the closest startTime (recommended startTime).

What I've got so far:

<?php
$array = array(    array("meeting_id" => "1812",  
                         "startTime" => "2016-10-07 14:30:00", 
                         "endTime" => "2016-10-07 14:35:00"),
                   array("meeting_id" => "1812",  
                         "startTime" => "2016-10-07 14:35:00", 
                         "endTime" => "2016-10-07 14:40:00"),
                   array("meeting_id" => "1812",  
                         "startTime" => "2016-10-07 14:40:00", 
                         "endTime" => "2016-10-07 14:45:00"),
                   array("meeting_id" => "1813",  
                         "startTime" => "2016-10-07 15:05:00", 
                         "endTime" => "2016-10-07 15:10:00"),
                   array("meeting_id" => "1813",  
                         "startTime" => "2016-10-07 15:10:00", 
                         "endTime" => "2016-10-07 15:15:00"),
                   array("meeting_id" => "1813",  
                         "startTime" => "2016-10-07 15:20:00", 
                         "endTime" => "2016-10-07 15:25:00"),
    );

arsort($array);
$firstTime = $array[0];
foreach($array as $key){
    if($firstTime["startTime"] > $key["endTime"]){
        // Do something in here.
    }
}

print_r($array);


?>

Printed Array:

Array
(
    [5] => Array
        (
            [meeting_id] => 1813
            [startTime] => 2016-10-07 15:20:00
            [endTime] => 2016-10-07 15:25:00
        )

    [4] => Array
        (
            [meeting_id] => 1813
            [startTime] => 2016-10-07 15:10:00
            [endTime] => 2016-10-07 15:15:00
        )

    [3] => Array
        (
            [meeting_id] => 1813
            [startTime] => 2016-10-07 15:05:00
            [endTime] => 2016-10-07 15:10:00
        )

    [2] => Array
        (
            [meeting_id] => 1812
            [startTime] => 2016-10-07 14:40:00
            [endTime] => 2016-10-07 14:45:00
        )

    [1] => Array
        (
            [meeting_id] => 1812
            [startTime] => 2016-10-07 14:35:00
            [endTime] => 2016-10-07 14:40:00
        )

    [0] => Array
        (
            [meeting_id] => 1812
            [startTime] => 2016-10-07 14:30:00
            [endTime] => 2016-10-07 14:35:00
        )

)

How I would expect it to work:

• Find the earliest start time for meeting_id == 1812, and then find the closest next meeting whose ID != 1812. However the start time of those meeting ID != 1812 needs to be greater than the selected end time of 1812

Answer 1

The following function will take your array as the first argument, and the Meeting ID as the second, and will in turn return the nearest meeting to the earliest meeting whose ID is not $id:

function get_nearest_meeting($meetings, $id)
{
    // Start by sorting the meetings:
    function sorter($a, $b)
    {
        return strtotime($a['startTime']) - strtotime($b['startTime']);
    }
    usort($meetings, 'sorter');

    foreach( $meetings as $meeting )
    {
        if( $meeting['meeting_id'] == $id)
        {
            $earliest = strtotime( $meeting['endTime'] );
            break;
        }
    }

    // Now loop over again and get the next meeting:
    foreach( $meetings as $meeting )
    {
        if( $meeting['meeting_id'] != $id && strtotime($meeting['startTime']) > $earliest)
        {
            return $meeting;
        }
    }
}

Given the following input (stored in $meetings):

Array
(
    [0] => Array
        (
            [errors] => 0
            [meeting_id] => 1812
            [id] => 31305
            [startTime] => 2016-10-07 14:00:00
            [endTime] => 2016-10-07 14:10:00
            [grade_id] => 87
        )

    [1] => Array
        (
            [errors] => 0
            [meeting_id] => 1813
            [id] => 31305
            [startTime] => 2016-10-07 14:10:00
            [endTime] => 2016-10-07 14:20:00
            [grade_id] => 87
        )

    [2] => Array
        (
            [errors] => 0
            [meeting_id] => 1812
            [id] => 31305
            [startTime] => 2016-10-07 14:10:00
            [endTime] => 2016-10-07 14:20:00
            [grade_id] => 87
        )

    [3] => Array
        (
            [errors] => 0
            [meeting_id] => 1812
            [id] => 31305
            [startTime] => 2016-10-07 14:20:00
            [endTime] => 2016-10-07 14:30:00
            [grade_id] => 87
        )

    [4] => Array
        (
            [errors] => 0
            [meeting_id] => 1813
            [id] => 31305
            [startTime] => 2016-10-07 14:20:00
            [endTime] => 2016-10-07 14:30:00
            [grade_id] => 87
        )

    [5] => Array
        (
            [errors] => 0
            [meeting_id] => 1815
            [id] => 31305
            [startTime] => 2016-10-07 14:30:00
            [endTime] => 2016-10-07 14:40:00
            [grade_id] => 87
        )

    [6] => Array
        (
            [errors] => 0
            [meeting_id] => 1812
            [id] => 31305
            [startTime] => 2016-10-07 14:30:00
            [endTime] => 2016-10-07 14:40:00
            [grade_id] => 87
        )

    [7] => Array
        (
            [errors] => 0
            [meeting_id] => 1813
            [id] => 31305
            [startTime] => 2016-10-07 14:30:00
            [endTime] => 2016-10-07 14:40:00
            [grade_id] => 87
        )

    [8] => Array
        (
            [errors] => 0
            [meeting_id] => 1815
            [id] => 31305
            [startTime] => 2016-10-07 14:40:00
            [endTime] => 2016-10-07 14:50:00
            [grade_id] => 87
        )

    [9] => Array
        (
            [errors] => 0
            [meeting_id] => 1813
            [id] => 31305
            [startTime] => 2016-10-07 14:40:00
            [endTime] => 2016-10-07 14:50:00
            [grade_id] => 87
        )

)

And calling it like this:

get_nearest_meeting($meetings, 1812);

We end up with the following result:

Array
(
    [errors] => 0
    [meeting_id] => 1813
    [id] => 31305
    [startTime] => 2016-10-07 14:10:00
    [endTime] => 2016-10-07 14:20:00
    [grade_id] => 87
)