将列添加到从平面关联查找数组映射的二维数组

Question

我有一个带有

brand_slug

键的计数关联数组和一个二维数组，我想向其中附加相关计数数据。

$countArray = [
    "abu-garcia" => 1,
    "daiwa" => 4,
    "shimano" => 4
];

$dataArray = [
    [
        "brand_id" => 36,
        "brand_name" => "Abu Garcia",
        "brand_slug" => "abu-garcia"
    ],
    [
        "brand_id" => 41,
        "brand_name" => "Daiwa",
        "brand_slug" => "daiwa"
    ],
    [
        "brand_id" => 41,
        "brand_name" => "Daiwa",
        "brand_slug" => "daiwa"
    ],
    [
        "brand_id" => 39,
        "brand_name" => "Shimano",
        "brand_slug" => "shimano"
    ],
    [
        "brand_id" => 39,
        "brand_name" => "Shimano",
        "brand_slug" => "shimano"
    ],
];

我想创建一个新数组，应如下所示：

[
    [
        "brand_id" => 36,
        "brand_name" => "Abu Garcia",
        "brand_slug" => "abu-garcia",
        "count" => 1
    ],
    [
        "brand_id" => 41,
        "brand_name" => "Daiwa",
        "brand_slug" => "daiwa",
        "count" => 4,
    ],
    [
        "brand_id" => 41,
        "brand_name" => "Daiwa",
        "brand_slug" => "daiwa",
        "count" => 4
    ],
    [
        "brand_id" => 39,
        "brand_name" => "Shimano",
        "brand_slug" => "shimano",
        "count" => 4
    ],
    [
        "brand_id" => 39,
        "brand_name" => "Shimano",
        "brand_slug" => "shimano",
        "count" => 4
    ],
];

Answer 1

我想我明白你想做什么......

如果这些是您的数组的示例：

$CountArray = array("abu-garcia"=>1,
                "daiwa"=>4,
                "shimano"=>4);
$DataArray = array(
            array("brand_id"=>36, "brand_name"=>"Abu Garcia", "brand_slug"=>"abu-garcia"),
            array("brand_id"=>41, "brand_name"=>"Daiwa", "brand_slug"=>"daiwa"),
            array("brand_id"=>39, "brand_name"=>"Shimano", "brand_slug"=>"shimano")
);

然后循环遍历第二个数组以构建一个新数组，并从第一个数组中添加

count

键，如下所示：

$i = 0;
foreach($DataArray as $ItemArray){
    foreach($ItemArray as $Key=>$Value){
        $NewArray[$i][$Key] = $Value;
        $NewArray[$i]['count'] = 0;
        if(isset($CountArray[$ItemArray['brand_slug']])){
            $NewArray[$i]['count'] = $CountArray[$ItemArray['brand_slug']];         
        }
    }
    ksort($NewArray[$i]);
    $i++;
}
print_r($NewArray);

Answer 2

您可以用最简单的方式这样做。 假设您的第一个数组名称是 $first_array，第二个数组名称是 $second_array。

就像循环第二个一样

foreach($second_array as $index => $item)
{
    $second_array[$index]['count'] = $first_array[$item['brand_slug']];
}

echo "<pre>";
print_r($second_array);

Answer 3

使用

array_map()

和数组联合运算符 (

+

) 可以最优雅地完成基于关联查找/映射数组向二维数组中的所有行添加新列的任务。

代码：（演示）

var_export(
    array_map(
        fn($row) => $row + ['count' => $countArray[$row['brand_slug']]],
        $dataArray
    )
);

在经典的

foreach()

循环中使用数组联合赋值运算符 (

+=

) 通过引用修改数据数组也没有任何问题。 (演示)

foreach ($dataArray as &$row) {
     $row += ['count' => $countArray[$row['brand_slug']]];
}
var_export($dataArray);

---

作为提问者的示例数据中未提出的考虑因素，如果在映射数组中找不到行的值，请使用空合并运算符回退到默认值。

`['count' => $map[$rowValue] ?? $someDefault]`

Answer 4

数组合并 将一个或多个数组的元素合并在一起，以便将其中一个的值附加到前一个数组的末尾。它返回结果数组。

示例 #array_merge() 示例

<?php
$array1 = array("color" => "red", 2, 4);
$array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
$result = array_merge($array1, $array2);
print_r($result);
?>