PHP : array_diff_key() function
PHP: Computes the difference of arrays using keys for comparison
The array_diff_key() function is used to compare the keys from an array against the keys from another array and returns the difference. This function is like array_diff() except the comparison is done on the keys instead of the values.
Version:
(PHP 4 and above)
Syntax:
array_diff(array1, array2, array3 ...)
Parameter:
| Name | Description | Required / Optional |
Type |
|---|---|---|---|
| array1 | The specified array which will be compared with other arrays. | Required | Array |
| array2 | Compared with the first array. | Required | Array |
| array3 | Compared with the second array. | Optional | Array |
Return value:
An array containing all the entries from array1 whose keys are not present in any of the other arrays i.e. array2, array3 etc..
Value Type: Array
Example:
<?php
$array1 = array('Math'=>77, 20, 'Geography'=>89, 'Language'=>67);
$array2 = array('Language'=>71, 'Science'=>91 ,20, 'Geography'=>89);
var_dump(array_diff_key($array1, $array2));
?>
Output:
array(1){["Math"]=> int(77) }
Pictorial Presentation:
View the example in the browser
Practice here online:
See also
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