what is the meaning of => while using arrays in php

Question

I have a php code.

$metadata = Array(
        'facebook'  => Array(
                'title'         => 'og:title',
                'type'          => 'og:type',
                'url'           => 'og:url',
                'thumbnail'     => 'og:image',
                'sitename'      => 'og:site_name',
                'key'           => 'fb:admins',
                'description'   => 'og:description'
            ),
        'google+'   => Array(
                'thumbnail'     => 'image',
                'title'         => 'name',
                'description'   => 'description'
            ),
        'twitter'   => Array(
                'card'          => 'twitter:card',
                'url'           => 'twitter:url',
                'title'         => 'twitter:title',
                'description'   => 'twitter:description',
                'thumbnail'     => 'twitter:image'
            )
    );

what does the => means. How to access an element in this array.

this is array .. $metadata['facebook']['type'] will give you 'og:type' — Eddie, Apr 03 '14 at 07:02
An array is a key/value store: when working with an array, the value ___before___ the `=>` is the `key`; the value ___after___ the `=>` is the `value` — Mark Baker, Apr 03 '14 at 07:03
@ShankarDamodaran: Actually, none of the questions linked from that reference (including that explicitly linked by @DaveChen) ask about the use of `=>` during array declaration. — eggyal, Apr 03 '14 at 07:17

score 0 · Answer 1 · answered Apr 03 '14 at 07:21

You have a multi dimensional array, so facebook, google and twitter are elements of the 1st dimension of the $metadata array and they are arrays themselves, here lies the multi dimension.

The => is just like an arrow pointing to the value/data.

To access the 1st dimension would be $metadata['twitter']; or $metadata[2]; it's the same statement, this would bring back the elements/keys of the twitter array.

To access the 2nd dimension would be $metadata['twitter']['card']; or $metadata[2][0]; again the two statements are the same, this would bring back the value of the element/key card

score 0 · Answer 2 · answered Apr 03 '14 at 07:22

what does the => means.

As documented under Arrays:
An array in PHP is actually an ordered map. A map is a type that associates values to keys.
```
[ deletia ]
```
An array can be created using the array() language construct. It takes any number of comma-separated key => value pairs as arguments.
```
array(
    key  => value,
    key2 => value2,
    key3 => value3,
    ...
)
```

How to access an element in this array.

As documented under Accessing array elements with square bracket syntax:

Array elements can be accessed using the array[key] syntax.

Example #6 Accessing array elements

<?php
$array = array(
    "foo" => "bar",
    42    => 24,
    "multi" => array(
         "dimensional" => array(
             "array" => "foo"
         )
    )
);

var_dump($array["foo"]);
var_dump($array[42]);
var_dump($array["multi"]["dimensional"]["array"]);
?>

The above example will output:

string(3) "bar"
int(24)
string(3) "foo"

what is the meaning of => while using arrays in php

2 Answers2

Example #6 Accessing array elements