Foreach With Square Bracket Syntax in PHP

Tutorial on how to traverse a Multidimensional array using php7.1 syntax

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Edited: 2021-03-07 10:03

Array destructuring with a loop, Square Bracket Syntax

PHP 7.1 introduced a useful new syntax to destructure an array into variables, and iterate over multidimensional arrays.

It involves the clever use of square brackets [ and ] inside a single foreach expression.

If the level of nesting is known, we can do with a single foreach loop—there is no longer a need to use nested loop structures to iterate over a multidimensional array. If we do not know the level of nesting before hand, we can still resort to old tactics. such as using a recursive function to loop over the array.

The syntax is best demonstrated in the below example:

foreach ($some_array as [
    'name' => $name,
    'email' => $email,
]) {
    // foreach expressions:
    echo $name . ':'. $email . PHP_EOL;
}

Brackets syntax for array destructuring

There is a few fully functioning examples included here in case you need it.

The example below uses the new bracket syntax on a 2-dimensional array:

$some_array[] = [
    'name' => 'JacobSeated',
    'email' => '[email protected]'
];
$some_array[] = [
    'name' => 'Rasmus',
    'email' => '[email protected]'
];


foreach ($some_array as [
    'name' => $name,
    'email' => $email,
]) {
    // foreach expressions:
    echo $name . ':'. $email . PHP_EOL;
}

Finally, if you have a 3-level array you would simply use the same syntax, as when assigning values to an array. The below may be used on a 3-dimensional array:

$some_array[] = [
    'name' => 'Sophia',
    'email' => '[email protected]',
    'more' => [
      'title' => 'I like cake',
      'content' => 'Lots of sugar'
    ]
];
$some_array[] = [
    'name' => 'Andrea',
    'email' => '[email protected]',
    'more' => [
      'title' => 'anything good and happy',
      'content' => 'I am content with using PHP'
    ]
];
foreach ($some_array as [
    'name' => $name,
    'email' => $email,
    'more' => [
      'content' => $content,
      'title' => $title
    ]])
{
    // Foreach expressions:
    echo $name . ':'. $content . PHP_EOL;
}

Brackets syntax for array destructuring

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