PHP array_intersect_assoc() Function
Quick summary: The PHP array_intersect_assoc() function compares the values and keys of two (or more) arrays, and returns the matches.
PHP array_intersect_assoc() Syntax
array_intersect_assoc(array $array, array ...$arrays): arrayPHP
PHP array_intersect_assoc() Basic examples
$a = ['a'=>1,'b'=>2];
$b = ['a'=>1,'b'=>3];
print_r(array_intersect_assoc($a,$b));PHP
Output:
Array ( [a] => 1 )Returns elements where both key and value match.
PHP array_intersect_assoc() Real-world usage
$permissions1=['read'=>true,'write'=>false];
$permissions2=['read'=>true,'write'=>true];
print_r(array_intersect_assoc($permissions1,$permissions2));PHP
Output:
Array ( [read] => 1 )Find shared permissions with same value.
PHP array_intersect_assoc() Edge cases
$a=['1'=>1];
$b=[1=>1];
print_r(array_intersect_assoc($a,$b));PHP
Output:
Array ( [1] => 1 )String and integer keys may be treated as equal.
PHP array_intersect_assoc() Common mistakes
Confusing with array_intersect()
array_intersect_assoc() compares keys and values.
Incorrect
array_intersect($a,$b);Correct
array_intersect_assoc($a,$b);Use correct function when keys matter.
PHP array_intersect_assoc() Frequently Asked Questions
What does array_intersect_assoc() do?
Computes intersection with index check.
Difference from array_intersect()?
Also compares keys.
Use case?
Strict matching.
Return type?
Array.
Common mistake?
Ignoring keys.
Performance?
Moderate.
Safe?
Yes.
Handles nested arrays?
No.
Alternative?
array_intersect().
Key sensitive?
Yes.
Best practice?
Use for strict comparisons.
Used in configs?
Yes.