PHP: How to compare keys in one array with values in another, and return matches?

Question

I have the following two arrays:

$array_one = array(\'colorZero\'=>\'black\', \'colorOne\'=>\'red\', \'colorTwo\'=>\'green\', \'colorThree\'=>\'b         


        

Answer 1

As of PHP 5.1 there is array_intersect_key (manual).

Just flip the second array from key=>value to value=>key with array_flip() and then compare keys.

So to compare OP's arrays, this would do:

$result = array_intersect_key( $array_one , array_flip( $array_two ) );

No need for any looping the arrays at all.