合并 2 个具有一些重复值的多维数组

Question

我有两个有时具有匹配键的数组，我需要根据匹配字段（品牌/型号/年份）合并这些值，并根据每个数组对象具有的值标志进行相应设置（在这种情况下，要么 适合：B 或适合：R)

第一个数组看起来像这样，包含 fit B：

$firstArray = [
 { Model: Aston Martin, Make: V12, Year: 2012, fit: B, front_fit: 52, rear_fit: null}
]

这是第二个数组，它只包含适合的 R：

$secondArray = [
 { Model: Aston Martin, Make: V12, Year: 2012, fit: R, front_fit: null, rear_fit: 24}
]

请注意大多数值是相同的，除了 fit 以及基于该标志（B 或 R）的前或后匹配。理想情况下，我想将这两个合并到一个新数组中，该数组将删除 fit 并相应地填写 front_fit 和 back_fit 字段：

$mergedNewArray = [
 { Model: Aston Martin, Make: V12, Year: 2012, front_fit: 52, rear_fit: 24}
]

可能会发生第三种情况，其中一个数组中可能没有匹配的模型/品牌/年份对象，如果是这种情况，我仍然想在新数组中包含现有记录

所以它会变成这样：

$mergedNewArray = [
 { Model: Aston Martin, Make: V12, Year: 2012, front_fit: 52, rear_fit: 24},
  //This has no matching object to merge with but should still be in this array
 { Model: Dodge, Make: Charger, Year: 2006, front_fit: null, rear_fit: 80} 
]

任何帮助将不胜感激，越少越好

编辑：为包含特定拟合的第一个数组和第二个数组添加了说明

Answer 1

可能最简单的方法是按品牌/型号/年份重新索引第一个数组，然后遍历第二个数组，查找相同的汽车，如果找到，更新记录，否则创建一个输出中的新条目。然后可以使用 array_values 以数字方式重新索引结果数组：

$firstArray = json_decode('[
 { "Model": "Aston Martin", "Make": "V12", "Year": 2012, "fit": "B", "front_fit": 52, "rear_fit": null },
 { "Model": "Aston Martin", "Make": "Vantage", "Year": 2017, "fit": "B", "front_fit": 40, "rear_fit": null }
]', true);

$secondArray =json_decode('[
 { "Model": "Aston Martin", "Make": "V12", "Year": 2012, "fit": "R", "front_fit": null, "rear_fit": 24 },
 { "Model": "Dodge", "Make": "Charger", "Year": 2006, "fit": "R", "front_fit": null, "rear_fit": 80 }
]', true);

$result = array();
// index the first array by the model, make and year
foreach ($firstArray as $car) {
    unset($car['fit']);
    $key = $car['Model'] . '#' . $car['Make'] . '#' . $car['Year'];
    $result[$key] = $car;
}

foreach ($secondArray as $car) {
    $key = $car['Model'] . '#' . $car['Make'] . '#' . $car['Year'];
    // have we seen this car?
    if (isset($result[$key])) {
        // if so, update
        $result[$key]['rear_fit'] = $car['rear_fit'];
    }
    else {
        // create a new entry
        unset($car['fit']);
        $result[$key] = $car;
    }
}
// reindex to numeric keys
$result = array_values($result);
print_r($result);

输出：

Array
(
    [0] => Array
        (
            [Model] => Aston Martin
            [Make] => V12
            [Year] => 2012
            [front_fit] => 52
            [rear_fit] => 24
        )
    [1] => Array
        (
            [Model] => Aston Martin
            [Make] => Vantage
            [Year] => 2017
            [front_fit] => 40
            [rear_fit] => 
        )
    [2] => Array
        (
            [Model] => Dodge
            [Make] => Charger
            [Year] => 2006
            [front_fit] => 
            [rear_fit] => 80
        )
)

Demo on 3v4l.org