Convert dot syntax like "this.that.other" to multi-dimensional array in PHP

Try this number...

function assignArrayByPath(&$arr, $path, $value, $separator='.') {
    $keys = explode($separator, $path);

    foreach ($keys as $key) {
        $arr = &$arr[$key];
    }

    $arr = $value;
}

CodePad

It will loop through the keys (delimited with . by default) to get to the final property, and then do assignment on the value.

If some of the keys aren't present, they're created.

You can use this function to convert dot notation arrray to multidimensional array.

function flattenToMultiDimensional(array $array, $delimiter = '.')
{
    $result = [];
    foreach ($array as $notations => $value) {
        // extract keys
        $keys = explode($delimiter, $notations);
        // reverse keys for assignments
        $keys = array_reverse($keys);

        // set initial value
        $lastVal = $value;
        foreach ($keys as $key) {
            // wrap value with key over each iteration
            $lastVal = [
                $key => $lastVal
            ];
        }
        
        // merge result
        $result = array_merge_recursive($result, $lastVal);
    }

    return $result;
}

Example:

$array = [
    'test.example.key' => 'value'
];

print_r(flattenToMultiDimensional($array));

Output:

Array
(
    [test] => Array
        (
            [example] => Array
                (
                    [key] => value
                )

        )

)

FYI In Laravel we have a array_set() helper function which translates in this function

Method to store in an array using dot notation

/**
 * Set an array item to a given value using "dot" notation.
 *
 * If no key is given to the method, the entire array will be replaced.
 *
 * @param  array   $array
 * @param  string  $key
 * @param  mixed   $value
 * @return array
 */
public static function set(&$array, $key, $value)
{
    if (is_null($key)) {
        return $array = $value;
    }

    $keys = explode('.', $key);

    while (count($keys) > 1) {
        $key = array_shift($keys);

        // If the key doesn't exist at this depth, we will just create an empty array
        // to hold the next value, allowing us to create the arrays to hold final
        // values at the correct depth. Then we'll keep digging into the array.
        if (! isset($array[$key]) || ! is_array($array[$key])) {
            $array[$key] = [];
        }

        $array = &$array[$key];
    }

    $array[array_shift($keys)] = $value;

    return $array;
}

It's simple as

$array = ['products' => ['desk' => ['price' => 100]]];

array_set($array, 'products.desk.price', 200);

// ['products' => ['desk' => ['price' => 200]]]

You may check it in the docs

If you need to instead get the data using dot notation the process is a bit longer, but served on a plate by array_get() which translates to this function (actually the linked source shows you all the helper array related class)

Method to read from an an array using dot notation

/**
 * Get an item from an array using "dot" notation.
 *
 * @param  \ArrayAccess|array  $array
 * @param  string  $key
 * @param  mixed   $default
 * @return mixed
 */
public static function get($array, $key, $default = null)
{
    if (! static::accessible($array)) {
        return value($default);
    }
    if (is_null($key)) {
        return $array;
    }
    if (static::exists($array, $key)) {
        return $array[$key];
    }
    if (strpos($key, '.') === false) {
        return $array[$key] ?? value($default);
    }
    foreach (explode('.', $key) as $segment) {
        if (static::accessible($array) && static::exists($array, $segment)) {
            $array = $array[$segment];
        } else {
            return value($default);
        }
    }
    return $array;
}

As you can see, it uses two submethods, accessible() and exists()

/**
 * Determine whether the given value is array accessible.
 *
 * @param  mixed  $value
 * @return bool
 */
public static function accessible($value)
{
    return is_array($value) || $value instanceof ArrayAccess;
}

And

/**
 * Determine if the given key exists in the provided array.
 *
 * @param  \ArrayAccess|array  $array
 * @param  string|int  $key
 * @return bool
 */
public static function exists($array, $key)
{
    if ($array instanceof ArrayAccess) {
        return $array->offsetExists($key);
    }
    return array_key_exists($key, $array);
}

Last thing it uses, but you can probably skip that, is value() which is

if (! function_exists('value')) {
    /**
     * Return the default value of the given value.
     *
     * @param  mixed  $value
     * @return mixed
     */
    function value($value)
    {
        return $value instanceof Closure ? $value() : $value;
    }
}

I would suggest using dflydev/dot-access-data.

If you're not familiar with using Composer, head over to https://getcomposer.org/ for an introduction so that you can download and autoload the package as as dependency for your project.

Once you have the package, you can load a multi-dimensional array into a Data object:

use Dflydev\DotAccessData\Data;

$data = new Data(array(
  's1' => array(
    't1' => array(
      'column' => array(
        '1' => 'size:33%',
      ),
    ),
  ),
);

And access the values using dot notation:

$size = $username = $data->get('s1.t1.column.1');