How can I select a subset of values from an array using the values from another array as keys? [duplicate]

Question

Here's my array of $keys:

Array
(
    [0] => 1
    [1] => 3
    [2] => 4
)

And my $values:

Array
(
    [0] => Red
    [1] => Orange
    [2] => Yellow
    [3] => Green
    [4] => Blue
)

I want to create a new array of some of the values in $values using the values in $keys as keys:

Array
(
    [1] => Orange
    [3] => Green
    [4] => Blue
)

Obviously I can foreach to get the values I want, but I want to make sure I'm not overlooking something in the plethora of PHP array functions.

I've Googled the question, and the answer comes back as using array_combine, which won't achieve the desired output.

Your help is appreciated :)

Might look at the second answer of the linked one in case there are duplicate values in the $keys array. — AbraCadaver
– AbraCadaver, Commented Apr 1, 2015 at 15:30

AbraCadaver · Accepted Answer · 2015-04-01 15:23:12Z

5

Flip the $keys array to make the values keys and then use array_intersect_key():

$result = array_intersect_key($values, array_flip($keys));

Returns the values from $values that have the same keys as the flipped $keys.

answered Apr 1, 2015 at 15:23

AbraCadaver

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2 Comments

Indeed, I don't understand why the OP does not want to use foreach?

@sємsєм: I don't have a problem with foreach, but if there's a built-in function to achieve the same goal, it's likely to be quicker, isn't it?