php: check if certain item in an array is empty

Question

In PHP, how would one check to see if a specified item (by name, I think - number would probably also work) in an array is empty?

Answer 1

if(empty($array['item']))

or

if(!isset($array['item']))

or

if(!array_key_exists('item', $array))

depending on what precisely you mean by "empty". See the docs for empty(), isset() and array_key_exists() as to what exactly they mean.

Answer 2

Types of empty (from PHP Manual). The following are considered empty for any variable:

• "" (an empty string)
• 0 (0 as an integer)
• "0" (0 as a string)
• NULL
• FALSE
• array() (an empty array)
• var $var; (a variable declared, but without a value in a class)

So take the example below:

$arr = array(
          'ele1' => 'test',
          'ele2' => false           
       );

1) $arr['ele3'] is not set. So:
isset($arr['ele3']) === false && empty($arr['ele3']) === true
it is not set and empty. empty() checks for whether the variable is set and empty or not.

2) $arr['ele2'] is set, but empty. So:
isset($arr['ele2']) === true && empty($arr['ele2']) === true

1) $arr['ele1'] is set and not empty:
isset($arr['ele1']) === true && empty($arr['ele1']) === false

if you wish to check whether is it empty, simply use the empty() function.