PHP 数组按值分组和最小-最大值

Question

我需要帮助在PHP中合并数组，我有这个数组，我正在尝试按模型分组项目，并合并年的最小值和最大值：

[0] => Array
(
[brand] => SUZUKI
[model] => GSF 1250 Bandit
[year] => 2006
)
[1] => Array
(
[brand] => SUZUKI
[model] => GSF 1250 Bandit
[year] => 2007
)
[2] => Array
(
[brand] => SUZUKI
[model] => GSF 1250 Bandit
[year] => 2008
)

[3] => Array
(
[brand] => SUZUKI
[model] => GSX 1250FA
[year] => 2011
)
[4] => Array
(
[brand] => SUZUKI
[model] => GSX 1250FA
[year] => 2012
)
[5] => Array
(
[brand] => SUZUKI
[model] => GSR 600
[year] => 2006
)
[6] => Array
(
[brand] => SUZUKI
[model] => GSR 600
[year] => 2007
)
[7] => Array
(
[brand] => SUZUKI
[model] => GSR 600
[year] => 2008
)

我想按模型对项目进行分组，并合并年份的最小值和最大值，如下所示：

[0] => Array
(
[brand] => SUZUKI
[model] => GSF 1250 Bandit
[year] => 2006 - 2008
)
[1] => Array
(
[brand] => SUZUKI
[model] => GSX 1250FA
[year] => 2011 - 2012
)
[2] => Array
(
[brand] => SUZUKI
[model] => GSR 600
[year] => 2006 -2008
)

我知道如何按型号对项目进行分组，但我无法实现合并年份：

foreach($array as $row){
$newArray[$row["model"]] = array(
"brand" => $row["brand"],
"model" => $row["model"],
"year" => $row["year"]
);
}

谢谢你的帮助。

Answer 1

这将其分为两个阶段，首先收集每个项目的最小和最大年份的数据。设置最小值和最大值时，它会检查以前的值(如果找不到则默认值(，并应用适当的min()或max()。。。

$newArray = [];
foreach($array as $row){
$newArray[$row["model"]] = array(
"brand" => $row["brand"],
"model" => $row["model"],
"minyear" => min($newArray[$row["model"]]["minyear"] ?? PHP_INT_MAX, $row["year"]),
"maxyear" => max($newArray[$row["model"]]["maxyear"] ?? PHP_INT_MIN, $row["year"]),
);
}

这会生成。。。

Array
(
[GSF 1250 Bandit] => Array
(
[brand] => SUZUKI
[model] => GSF 1250 Bandit
[minyear] => 2006
[maxyear] => 2008
)
[GSX 1250FA] => Array
(
[brand] => SUZUKI
[model] => GSX 1250FA
[minyear] => 2011
[maxyear] => 2012
)
)

然后，您可以处理它，以您想要的格式提供年份(删除不再使用的字段(。。。

foreach ( $newArray as &$row )  {
$row['year'] = $row['minyear'] . " - ". $row['maxyear'];
unset ( $row['minyear'], $row['maxyear'] );
}

它产生。。。

Array
(
[GSF 1250 Bandit] => Array
(
[brand] => SUZUKI
[model] => GSF 1250 Bandit
[year] => 2006 - 2008
)
[GSX 1250FA] => Array
(
[brand] => SUZUKI
[model] => GSX 1250FA
[year] => 2011 - 2012
)
)