Parse string in order to get array elements [duplicate]

Question

I'm trying to figure out how to take a string, parse it, and get the corresponding array values that match the parsed keys back. I don't know how to properly explain this, so here's an example.

$testArray = array(
    'router' => array(
        'format' => 'xml',
    ),
);

The string I want to parse will look like this - router.format, and I'm obviously expecting back xml as a string. The passed in string can have any arbitrary amount of separating periods. I was thinking of doing recursion somehow, but I can't think of any way in which this will work.

This is very similar to SF2's service container and the way in which you get services back.

Any help would be great!

You could split them using explode()? This will return an array based on a split delimiter — iswinky
– iswinky, Commented Aug 4, 2014 at 20:09
Yeah I know I can explode(), but that will simply return an array containing router and format - what then? I want to use those values to get back the format key from the router array from within the $testArray... — iLikeBreakfast
– iLikeBreakfast, Commented Aug 4, 2014 at 20:11
How do you want to handle the cases where the string has more or fewer parts than there are levels in the array? — Patrick Q
– Patrick Q, Commented Aug 4, 2014 at 20:11
I am a bit confused by what you are asking. It might help if you post some code showing what you might have tried so far. — Mr. Concolato
– Mr. Concolato, Commented Aug 4, 2014 at 20:19

AbraCadaver · Accepted Answer · 2014-08-04 20:19:38Z

3

Might need some error checking:

$testArray = array(
    'router' => array(
        'format' => 'xml',
    ),
);
$path = 'router.format';

$result = $testArray;
foreach(explode('.', $path) as $key) {
    if(isset($result[$key])) {
        $result = $result[$key];
    }
}
print_r($result);

answered Aug 4, 2014 at 20:19

AbraCadaver

79.2k7 gold badges75 silver badges91 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

iLikeBreakfast Over a year ago

Exactly what I wanted! Simple and elegant. Thanks!

fiction Over a year ago

It's will fail if you will have array like this: $testArray = array( 'format' => 'fail' );

AbraCadaver Over a year ago

@fiction: Ummm... No.

fiction · Accepted Answer · 2014-08-04 20:16:59Z

1

<?php
    $string = 'router.format';
    $array = array(
        'router' => array(
            'format' => 'xml',
        ),
    );

    $string = explode('.', $string);
    $result = $array;

    for($i = 0; $i < count($string); ++$i)
    {  
        $key = $string[$i];
        if(isset($result[$key]))
            $result = $result[$key];
        else
            break;
    }

    print_r($result);

answered Aug 4, 2014 at 20:16

fiction

5781 gold badge6 silver badges22 bronze badges

Comments

dave · Accepted Answer · 2014-08-04 20:18:24Z

1

Laravel has a helper function which does this: http://laravel.com/api/source-function-array_get.html#226-251

The code for the function is:

function array_get($array, $key, $default = null)
{
    if (is_null($key)) return $array; 
    if (isset($array[$key])) return $array[$key];
    foreach (explode('.', $key) as $segment)
    {
         if ( ! is_array($array) or ! array_key_exists($segment, $array))
         {
             return value($default);
         }

         $array = $array[$segment];
    }

    return $array;
}

function value($value)
{
     return $value instanceof Closure ? $value() : $value;
}

Usage:

array_get($testArray, 'router.format');

answered Aug 4, 2014 at 20:18

dave

65.1k6 gold badges81 silver badges98 bronze badges

Comments

shudder · Accepted Answer · 2014-08-04 22:22:46Z

0

Recursive method.

function array_path($keys, $array) {
    $key = array_shift($keys);
    if (!isset($array[$key])) { return false; }
    return !empty($keys) ? array_path($keys, $array[$key]) : $array[$key];
}

$testArray = array(
    'router' => array(
        'format' => 'xml',
    ),
);
$keys = explode('.', 'router.format');

var_dump(array_path($keys, $testArray));

answered Aug 4, 2014 at 22:22

shudder

2,1012 gold badges20 silver badges21 bronze badges

Collectives™ on Stack Overflow

Parse string in order to get array elements [duplicate]

4 Answers 4

3 Comments

Comments

Comments

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

3 Comments

Comments

Comments

Comments

Linked

Related