48

Just as the title implies, I am trying to create a parser and trying to find the optimal solution to convert something from dot namespace into a multidimensional array such that

s1.t1.column.1 = size:33%

would be the same as

$source['s1']['t1']['column']['1'] = 'size:33%';
BoltClock
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Bryan Potts
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9 Answers9

62

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.

alex
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    for the record, this would be the complementary variant: http://stackoverflow.com/a/10424516/1388892 – Adrian Föder Mar 17 '14 at 10:32
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    There is a bug in this function. Because of the "while" evaluation, if there is a 0 in the path it will break the cycle: abc.0.bac.1 Will produce: $arr['abc'] only. To fix, just replace the first line with while () ... to a foreach cycle. Also, adding a forth parameter $separator to it will make it much more useful for different cases (e.g. when you have underscore or dashes): function assignArrayByPath(&$arr, $path, $value, $separator='.') { $keys = explode($separator, $path); foreach($keys AS $key) { $arr = &$arr[$key]; } $arr = $value; } – Pavel Bogatinov Jan 14 '16 at 15:19
  • @PavelBogatinov Agree on those points, I will edit the answer. – alex Feb 24 '16 at 08:32
36

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;
    }
}
phaberest
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5

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
                )

        )

)
Erkin Eren
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1

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');
grasmash
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0

After more than a decade nobody has actually answered the question of converting string x to array y. The accepted answer came closest, but still assumes an existing array and requires a separate value.

I needed to do just this in a quick one-off script, so my answer does what the question asked, while allowing some customization of separators, and basic error checking:

<?php
function dotKvToArray(string $kv, string $kv_sep = "=", string $arr_sep = "."): array
{
    // split on the equal sign (if it's there)
    [$keystring, $value] = str_contains($kv, $kv_sep)
        ? explode($kv_sep, $kv, 2)
        : [$kv, ""];

    // return early for empty string
    if (trim($keystring) === "") {
        return [];
    }

    // reverse the array keys and assign the array to each sequentially
    // the first one will get the value assigned instead
    foreach (array_reverse(explode($arr_sep, trim($keystring))) as $key) {
        $ret = [$key => $ret ?? trim($value)];
    }

    // return the array, or an empty array in case somehow the loop was missed
    return $ret ?? [];
}

$source = dotKvToArray("s1.t1.column.1 = size:33%");
echo json_encode($source);

Output:

{"s1":{"t1":{"column":{"1":"size:33%"}}}}
miken32
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  • The ternary expression and the typing on `$kv` in the function signature ensure that `$keystring` is always defined and always a string. Though I wasn’t using numeric keys, getting rid of `empty()` is probably a good idea anyway since “0” is falsy. – miken32 Apr 05 '23 at 13:51
-2

Although pasrse_ini_file() can also bring out multidimensional array, I will present a different solution. Zend_Config_Ini()

$conf = new Zend_COnfig_Ini("path/to/file.ini");
echo $conf -> one -> two -> three; // This is how easy it is to do so
//prints one.two.three
Starx
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-3

I found a solution that worked for me at: Convert Flat PHP Array to Nested Array based on Array Keys and since I had an array based on an .ini file with different keys I made a tiny modification of that script and made work for me.

My array looked like this:

[resources.db.adapter] => PDO_MYSQL
[resources.db.params.host] => localhost
[resources.db.params.dbname] => qwer
[resources.db.params.username] => asdf
...

On request, this is the code that I described was working for me:

<?php
echo "remove the exit :-)"; exit;
$db_settings = parse_ini_file($_SERVER['DOCUMENT_ROOT'].'/website/var/config/app.ini');

echo "<pre>";
print_r($db_settings);
echo "</pre>";

$resources = array();

foreach ($db_settings as $path => $value) {
  $ancestors = explode('.', $path);
  set_nested_value($resources, $ancestors, $value);
}
echo "<pre>";
print_r($resources);
echo "</pre>";

/**
 * Give it and array, and an array of parents, it will decent into the
 * nested arrays and set the value.
 */
function set_nested_value(array &$arr, array $ancestors, $value) {
  $current = &$arr;
  foreach ($ancestors as $key) {

    // To handle the original input, if an item is not an array, 
    // replace it with an array with the value as the first item.
    if (!is_array($current)) {
      $current = array( $current);
    }

    if (!array_key_exists($key, $current)) {
      $current[$key] = array();
    }
    $current = &$current[$key];
  }

  $current = $value;
}

This is the source of the .ini file read by the parse_ini_file():

Array
(
    [resources.db.adapter] => PDO_MYSQL
    [resources.db.params.host] => localhost
    [resources.db.params.dbname] => dbname
    [resources.db.params.username] => dbname_user
    [resources.db.params.password] => qwerqwerqwerqwer
    [resources.db.params.charset] => utf8
    [externaldb.adapter] => PDO_MYSQL
    [externaldb.params.host] => localhost
    [externaldb.params.dbname] => dbname2
    [externaldb.params.username] => dbname_user2
    [externaldb.params.password] => qwerqwerwqerqerw
    [externaldb.params.charset] => latin1
)

This is the outcome of the code above:

Array
(
    [resources] => Array
        (
            [db] => Array
                (
                    [adapter] => PDO_MYSQL
                    [params] => Array
                        (
                            [host] => localhost
                            [dbname] => dbname
                            [username] => dbname_user
                            [password] => qwerqwerqwerqwer
                            [charset] => utf8
                        )

                )

        )

    [externaldb] => Array
        (
            [adapter] => PDO_MYSQL
            [params] => Array
                (
                    [host] => localhost
                    [dbname] => dbname2
                    [username] => dbname_user2
                    [password] => qwerqwerwqerqerw
                    [charset] => latin1
                )

        )
)  
orjtor
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-4

I am pretty sure you are trying to do this to store some configuration data or similar.

I highly suggest you to save such file as .ini and use parse_ini_file() function to change the configuration data into a multidimensional array. As simple as this

$confArray = parse_ini_file("filename.ini"); 
var_dump($confArray);
Starx
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-4

Quick and dirty...

<?php

$input = 'one.two.three = four';

list($key, $value) = explode('=', $input);
foreach (explode('.', $key) as $keyName) {
    if (false === isset($source)) {
        $source    = array();
        $sourceRef = &$source;
    }
    $keyName = trim($keyName);
    $sourceRef  = &$sourceRef[$keyName];
}
$sourceRef = $value;
unset($sourceRef);
var_dump($source);
Lloyd Watkin
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