How to filter an array by a condition

Question

I have an array like this:

array(\"a\" => 2, \"b\" => 4, \"c\" => 2, \"d\" => 5, \"e\" => 6, \"f\" => 2)

Now I want to fi

Answer 1

This should work, but I'm not sure how efficient it is as you probably end up copying a lot of data.

$newArray = array_intersect_key(
                  $fullarray, 
                  array_flip(array_keys($fullarray, 2))
            );