How to merge multiple arrays into one array according to specified key names in PHP

WBOY
Release: 2023-07-07 16:16:02
Original
1403 people have browsed it

How to merge multiple arrays into one array according to the specified key name in PHP

In development, we often encounter the need to merge multiple arrays into one array according to the specified key name. This need is very common when working with data, especially when working with database result sets, for example. This article will introduce several common methods to achieve this function and give corresponding code examples.

Method 1: Use loop traversal

The simplest method is to use a loop to traverse all arrays and add the corresponding values ​​to the new array according to the specified key name. The sample code is as follows:

function mergeArrays($key, ...$arrays)
{
    $result = [];
    
    foreach ($arrays as $array) {
        if (isset($array[$key])) {
            $result[] = $array[$key];
        }
    }
    
    return $result;
}

$array1 = ['id' => 1, 'name' => 'Alice'];
$array2 = ['id' => 2, 'name' => 'Bob'];
$array3 = ['id' => 3, 'name' => 'Charlie'];

$result = mergeArrays('name', $array1, $array2, $array3);

print_r($result);
Copy after login

Run the above code, the output result is:

Array
(
    [0] => Alice
    [1] => Bob
    [2] => Charlie
)
Copy after login
Copy after login
Copy after login

Method 2: Use array_map function

array_map function can apply a callback function to multiple arrays on and returns a new array. We can use this function to merge multiple arrays. The sample code is as follows:

function mergeArrays($key, ...$arrays)
{
    $callback = function ($array) use ($key) {
        return $array[$key] ?? null;
    };
    
    $result = array_map($callback, $arrays);
    
    return array_filter($result, function($value) {
        return $value !== null;
    });
}

$array1 = ['id' => 1, 'name' => 'Alice'];
$array2 = ['id' => 2, 'name' => 'Bob'];
$array3 = ['id' => 3, 'name' => 'Charlie'];

$result = mergeArrays('name', $array1, $array2, $array3);

print_r($result);
Copy after login

Run the above code, the output result is:

Array
(
    [0] => Alice
    [1] => Bob
    [2] => Charlie
)
Copy after login
Copy after login
Copy after login

Method 3: Use array_reduce function

array_reduce function is used to iterate the elements in the array , process them according to the specified callback function, and return a final result. We can use this function to merge multiple arrays. The sample code is as follows:

function mergeArrays($key, ...$arrays)
{
    $callback = function ($result, $array) use ($key) {
        if (isset($array[$key])) {
            $result[] = $array[$key];
        }
        return $result;
    };
    
    $result = array_reduce($arrays, $callback, []);
    
    return $result;
}

$array1 = ['id' => 1, 'name' => 'Alice'];
$array2 = ['id' => 2, 'name' => 'Bob'];
$array3 = ['id' => 3, 'name' => 'Charlie'];

$result = mergeArrays('name', $array1, $array2, $array3);

print_r($result);
Copy after login

Run the above code, the output result is:

Array
(
    [0] => Alice
    [1] => Bob
    [2] => Charlie
)
Copy after login
Copy after login
Copy after login

The above are examples of several common methods to merge multiple arrays into one array according to the specified key name. Choosing the appropriate method according to the actual situation can greatly improve the efficiency and readability of the code. Hope this helps!

The above is the detailed content of How to merge multiple arrays into one array according to specified key names in PHP. For more information, please follow other related articles on the PHP Chinese website!

source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template
About us Disclaimer Sitemap
php.cn:Public welfare online PHP training,Help PHP learners grow quickly!