PHP Array_intersect_key ()

Definition and usage

The Array_intersect_key () function computes the intersection of an array using the key name comparison.

Array_intersect_key () returns an array that contains all the values of the key names that appear in the array being compared and that appear in all other parameter arrays.

Note: Only key names are used for comparisons.

Grammar

Array_intersect_key (Array1,array2,array3 ...)

Parameters	Describe
Array1	Necessary. The first array to compare with the other array.
Array2	Necessary. The array to compare with the first array.
Array3	Optional. The array to compare with the first array. Can have more than one.

Example 1

<?php$a1 = Array (0=> "cat",1=> "Dog",2=> "Horse"), $a 2 = Array (2=> "Bird",0=> "Cat",4=> "Fish"); Print_r (Array_intersect_key ($a 1, $a 2));? >

Output:

Array ([0] = Cat [2] = Horse)

Example 2

<?php$a1 = Array (0=> "Cat",1=> "Dog",2=> "Horse"), $a 2 = Array (2=> "Bird",3=> "Rat",4=> "Fish"); $a 3 = Array (2=> "Dog",6=> "Cow",7=> "Bird");p Rint_r (Array_intersect_key ($a 1, $a 2, $a 3)); >

Output:

Array ([2] = Horse)

　　

PHP Array_intersect_key ()