Replace certain items within multidimensional array

Question

I have an array that can vary in how many arrays deep there are, for example:

        array(
              'one' => array(
                             array(
                                'something' => 'value'
                                ),
                             array(
                                'something2' => 'value2'
                                ),
                             'another' => 'anothervalue'
                             ),
              'two' =>  array(
                             array(
                                'something' => 'value'
                                ),
                             array(
                                'something2' => 'value2'
                                ),
                             'another' => 'anothervalue'
                             )
              )

Now, let's say I want to replace everything with the key 'something'.

Would I need to use a recursive function to iterate through the array? or is there a better way?

Thank you!

Answer 1

Have a look at array_walk_recursive. It may be quite handy in a situation like this.

Here's an example using array_walk_recursive:

$arr = array(
      'one' => array(
            array('something' => 'value'),
            array('something2' => 'value2'),
            'another' => 'anothervalue'
            ),
      'two' =>  array(
            array('something' => 'value'),
            array('something2' => 'value2'),
            'another' => 'anothervalue'
            )
       );

function update_something(&$item, $key)
{
    if($key == 'something')
        $item = 'newValue';
}

array_walk_recursive($arr, 'update_something');

If used inside a class the callback method have to add the object along with the function. This is achieved with an array:

array_walk_recursive($arr, array($this, 'update_something'));

Answer 2

This is a function that you can either be used as a global function or you just put it into a class:

/**
 * replace any value in $array specified by $key with $value
 *
 * @return array array with replaced values
 */
function replace_recursive(Array $array, $key, $value)
{
    array_walk_recursive($array, function(&$v, $k) use ($key, $value)
        {$k == $key && $v = $value;});
    return $array;
}

# usage:
$array = replace_recursive($array, 'something', 'replaced');

It's also making use of array_walk_recursive but encapsulated. The key and the value can be specified as function parameters and not hardencoded in some callback, so it's more flexible.