PHP-检查一个数组中的值是否存在于另一个数组多维数组中

Question

I have the following two arrays.

This is a flat array (string: $second_names):

Array ( [0] => Cars [3] => Bikes [8] => Trucks ) //$second_names

I have this multidimensional array - (string: $premiumCatArraySets):

Array
(
    [0] => Array
        (
            [primary-category] => Automobiles
            [secondary-category] => Cars
            [tertiary-category] => Fiat Punto
        )
[1] => Array
    (
        [primary-category] => Automobiles
        [secondary-category] => Cars
        [tertiary-category] => BMW
    )

[2] => Array
    (
        [primary-category] => Automobiles
        [secondary-category] => Bikes
        [tertiary-category] => Honda
    )

[4] => Array
    (
        [primary-category] => Automobiles
        [secondary-category] => Trucks
        [tertiary-category] => Iveco
    )

[6] => Array
    (
        [primary-category] => Automobiles
        [secondary-category] => Cars
        [tertiary-category] => Mercedes
    )

[9] => Array
    (
        [primary-category] => Automobiles
        [secondary-category] => Cars
        [tertiary-category] => Toyota
    )

I am trying to use in_array to see whether the values in the flat array exist and output the brand of the car.

This is what I tried

foreach ($second_names as $second_name) {//Vechile type e.g. car, truck, bike
    if(in_array($second_name, $premiumCatArraySets)){
        echo '<h2>'.$second_name.'</h2>';
        foreach ($third_names as $third_name) {// e.g. Fiat, BMW, Toyota
            echo $third_name.'<br/>';
        }
    }
}

The line for if(in_array($second_name, $premiumCatArraySets)){ doesn't seem to be displaying anything.

Answer 1

If my understanding is correct, you have to get the vehicle brand from the second array for each vehicles in the first array. You could do something like below. This is a basic script.

<?php

$vehicles = ['Cars', 'Bikes', 'Trucks'];

$details = [
    [
        'primary-category' => 'Automobiles',
        'secondary-category' => 'Cars',
        'tertiary-category' => 'BMW'
    ],
    [
        'primary-category' => 'Automobiles',
        'secondary-category' => 'Trucks',
        'tertiary-category' => 'Benz'
    ]
];

foreach ($vehicles as $vehicle) {
    foreach ($details as $detail) {
        if ($vehicle == $detail['secondary-category']) {
            echo $detail['tertiary-category'];
            break;
        }
    }
}

?>

Answer 2

Try

$output = [];
foreach($premiumCatArraySets as $key => $value){    
    if(in_array($value["secondary-category"],$second_names)){
        if(!isset($output[$value["secondary-category"]])){
            $output[$value["secondary-category"]]  = [];
        }        
        $output[$value["secondary-category"]][] = $value["tertiary-category"];
    }
}
foreach($output as $key => $value){ 
    echo '<h2>'.$key."</h2>";
        echo implode(", ",$value)."<br/>";
}

---

Output

Cars    
Fiat Punto, BMW, Mercedes, Toyota

Bikes    
Honda

Trucks    
Iveco

Refer : Demo

Answer 3

The solution using call_user_func_array , array_merge_recursive , array_keys , array_flip , array_intersect_key and implode functions:

// grouping each category preserving the position of each item
$groups = call_user_func_array('array_merge_recursive', $premiumCatArraySets);
foreach ($second_names as $name) {
    $indexes = array_flip(array_keys($groups['secondary-category'], $name));
    echo '<h2>'.$name.'</h2>';
    echo implode(", ", array_intersect_key($groups['tertiary-category'], $indexes)) .'<br/>';
}

The output:

 <h2>Cars</h2>Fiat Punto, BMW, Mercedes, Toyota<br/><h2>Bikes</h2>Honda<br/><h2>Trucks</h2>Iveco<br/>