Use PHP custom functions to extend the functionality of array intersection and union

Array intersection and union functionality can be extended using PHP custom functions, custom intersection functions allow finding intersections by key or value, and custom union functions find unions by key or value. This gives you the flexibility to manipulate arrays based on your specific needs.

Use PHP custom functions to extend array intersection and union

In PHP, intersection and union are two common Data manipulation functions to use. However, sometimes we need to extend its functionality to meet specific needs. This tutorial guides you through creating custom functions using PHP to enhance intersection and union processing.

Custom Intersection Function

Custom intersection function allows you to specify the key or value of the intersection you want to find. Here's how to create it:

function custom_array_intersect(array $array1, array $array2, $key_or_value = 'key')
{
    $result = [];
    foreach ($array1 as $key => $value) {
        if ($key_or_value == 'key') {
            if (array_key_exists($key, $array2)) {
                $result[$key] = $array1[$key];
            }
        } else {
            if (in_array($value, $array2)) {
                $result[$key] = $array1[$key];
            }
        }
    }
    return $result;
}

Custom Union Function

Similarly, you can create a custom union function that allows you to specify the keys to find the union on Or value:

function custom_array_union(array $array1, array $array2, $key_or_value = 'key')
{
    $result = [];
    foreach ($array1 as $key => $value) {
        $result[$key] = $array1[$key];
    }
    foreach ($array2 as $key => $value) {
        if ($key_or_value == 'key') {
            if (!array_key_exists($key, $result)) {
                $result[$key] = $array2[$key];
            }
        } else {
            if (!in_array($value, $result)) {
                $key_to_use = array_search($value, $array1);
                if ($key_to_use !== false) {
                    $result[$key_to_use] = $array2[$key];
                } else {
                    $new_key = max(array_keys($result)) + 1;
                    $result[$new_key] = $array2[$key];
                }
            }
        }
    }
    return $result;
}

Practical case

The following are some practical cases of two custom functions:

Intersection example:

$array1 = ['a' => 1, 'b' => 2, 'c' => 3];
$array2 = ['b' => 4, 'c' => 5, 'd' => 6];

$result = custom_array_intersect($array1, $array2, 'key');
print_r($result); // 输出： ['b' => 4, 'c' => 5]

Union example:

$array1 = ['a' => 1, 'b' => 2, 'c' => 3];
$array2 = ['b' => 4, 'd' => 5, 'e' => 6];

$result = custom_array_union($array1, $array2, 'key');
print_r($result); // 输出： ['a' => 1, 'b' => 4, 'c' => 3, 'd' => 5, 'e' => 6]

The above is the detailed content of Use PHP custom functions to extend the functionality of array intersection and union. For more information, please follow other related articles on the PHP Chinese website!