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.
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