PHP根据值的组合合并两个数组

Question

I have below two arrays:

$a = Array {
    [0] => Array {
        [code] => '123',
        [name] => 'ABC'
    },
    [1] => Array {
        [code] => '456',
        [name] => 'XYZ'
    }
}

$b = Array {
    [0] => Array {
        [code] => '123',
        [name] => 'ABC',
        [price] => '34'
    },
    [1] => Array {
        [code] => '456',
        [name] => 'PQR',
        [price] => '56'
    },
    [2] => Array {
        [code] => '456',
        [name] => 'XYZ',
        [price] => '90'
    }
}

I want to create a third array where in the combination of code and name matches, like this:

$c = Array {
    [0] => Array {
        [code] => '123',
        [name] => 'ABC',
        [price] => '34'
    },
    [1] => Array {
        [code] => '456',
        [name] => 'XYZ',
        [price] => '90'
    }
}

I don't want the second array of $b to be considered since the combination of code and name in that does not match with the one in array $a Please help!

Answer 1

Your data structures are not built well for the required comparison. It would be easier if both of the arrays had "compound keys" instead of indexes. I mean, if the rows in the arrays looked like '123_ABC' => ['code' => '123', 'name' => 'ABC',] then making direct key-based comparisons would be a breeze.

Using what you have and with the intention of reducing the total iterations over the arrays, I recommend nested loops with early breaks in the inner loop as soon as a match is found.

Code: ( Demo )

$whiteList = [
    ['code' => '123', 'name' => 'ABC',],
    ['code' => '456', 'name' => 'XYZ',],
];

$pricedList = [
    ['code' => '123', 'name' => 'ABC', 'price' => '34'],
    ['code' => '456', 'name' => 'PQR', 'price' => '56'],
    ['code' => '456', 'name' => 'XYZ', 'price' => '90'],
    ['code' => '456', 'name' => 'GHI', 'price' => '70'],
];

$result = [];
foreach ($whiteList as $whiteRow) {
    foreach ($pricedList as $pricedRow) {
        if ($whiteRow['code'] === $pricedRow['code'] && $whiteRow['name'] === $pricedRow['name']) {
            $result[] = $pricedRow;
            continue 2;  // no reason to keep iterating inner loop after match is found
        }
    }
}
var_export($result);

Output:

array (
  0 => 
  array (
    'code' => '123',
    'name' => 'ABC',
    'price' => '34',
  ),
  1 => 
  array (
    'code' => '456',
    'name' => 'XYZ',
    'price' => '90',
  ),
)