php - 在 PHP 中按多维数组分组并用逗号连接结果(不创建不必要的逗号)

Question

我需要按两列对二维数组中的行进行分组，然后在每组中，我需要用逗号连接另一列的值。

请注意，在第三行中，诊断值为空。

$data = [
  ["id" => 1, "begin" => "01/01", "diagnostic" => "a"],
  ["id" => 1, "begin" => "01/01", "diagnostic" => "b"],
  ["id" => 1, "begin" => "01/01", "diagnostic" => ""],
  ["id" => 1, "begin" => "02/02", "diagnostic" => "a"],
];

预期结果:

[
  ["id" => 1, "begin" => "01/01", "diagnostic" => "a, b"],
  ["id" => 1, "begin" => "02/02", "diagnostic" => "a"],
]

Answer 1

公平地说，您要求的是一个完整的解决方案。

下面是我对如何完成它的快速理解:

http://sandbox.onlinephpfunctions.com/code/eb4fef6146b77fb7ff157790046c79750ef90cdb

<?php
$data = [
  0 =>array("id"=>1, "begin"=>"01/01","diagnostic"=>"a", "procedure" => "x"),
  1 =>array("id"=>1, "begin"=>"01/01","diagnostic"=>"b", "procedure" => ""),
  2 =>array("id"=>1, "begin"=>"01/01","diagnostic"=>"a", "procedure" => "y"),
  3 =>array("id"=>1, "begin"=>"02/02","diagnostic"=>"a", "procedure" => "z"),
];

// create an empty array to hold results
$result = [];

// iterate through each entry of the original $data
foreach($data as $entry){
    // create a temporary array index, that will be unique across the entries conditions (begin, id)
    $tempId = $entry['id'] . '-' . $entry['begin'];

    // create and append entries to diagnostic and procedure
    $result[$tempId]['diagnostic'][] = $entry['diagnostic'];
    $result[$tempId]['procedure'][] = $entry['procedure'];

    // copy data that is identical
    $result[$tempId]['begin'] = $entry['begin'];
    $result[$tempId]['id'] = $entry['id'];
}

// iterate through entries and implode unique, not empty elements of diagnostic and procedure array with a comma
foreach($result as &$entry){
    $entry['diagnostic'] = implode(',', array_unique(array_filter($entry['diagnostic'])));
    $entry['procedure'] = implode(',', array_unique(array_filter($entry['procedure'])));
}
print_r($result);

以上将产生:

Array
(
    [1-01/01] => Array
        (
            [diagnostic] => a,b
            [procedure] => x,y
            [begin] => 01/01
            [id] => 1
        )

    [1-02/02] => Array
        (
            [diagnostic] => a
            [procedure] => z
            [begin] => 02/02
            [id] => 1
        )

)