Select array values based on another array

Question

I have 2 arrays : “Array-List” and “Array-Criteria” :

Array-List
(
    [1] => APPLE
    [2] => BANANA
    [3] => ORANGE
    [4] => LEMON
)

Array-Criteria
(
    [0] => 1
    [1] => 3
)

Is there a quick way (my Array-List can consist of thousands of entries) to select the values from Array-List based on Array-Criteria without looping through Array-List in PHP?

What is the expected result? Have you had a look at `array_filter`? — Nico Haase, Oct 10 '18 at 15:01
`$arrayList[$arrayCriteria[1]]` => "Orange" - Is that what you mean? If not: How is criteria else connected to the list? — Jeff, Oct 10 '18 at 15:01
what are you actually looking for? Select what values? How do the arrays link up? — treyBake, Oct 10 '18 at 15:02
If it would be SQL, it would be SELECT value FROM Array-List WHERE key IN (SELECT value FROM Array-Criteria) — flaggalagga, Oct 10 '18 at 15:05

Gufran Hasan · Accepted Answer · 2018-10-10T15:14:46.003

2

Use array_intersect_key and array_flip functions to get data as:

$arr1 = Array-List
(
    [1] => APPLE
    [2] => BANANA
    [3] => ORANGE
    [4] => LEMON
)

$arr2 = Array-Criteria
(
    [0] => 1
    [1] => 3
)



var_dump(array_intersect_key($arr1, array_flip($arr2)));

edited Oct 10 '18 at 15:14

answered Oct 10 '18 at 15:03

Gufran Hasan

8,910
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Thank you so very much. This was exactly what I was looking for ! – flaggalagga Oct 10 '18 at 15:13

Nigel Ren · Answer 2 · 2018-10-10T15:28:18.607

0

If you loop over the criteria, you can build a list of the macthing items...

$selected = [];
foreach ( $arrayCriteria as $element ) {
    $selected[] = $arrayList[$element];
}

Then $selected will be a list of the items your after.

Also in a quick test, it's about twice as fast as using the array_ methods.

edited Oct 10 '18 at 15:28

answered Oct 10 '18 at 15:05

Nigel Ren

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True, but it's still a loop involved. I think Gufran Hasan's solution is slicker. – flaggalagga Oct 10 '18 at 15:16
Not disagreeing with the other answer being good, but any solution will involve a loop. – Nigel Ren Oct 10 '18 at 15:18
I did some speed tests and array_intersect_key solution seems to be the fastest. – flaggalagga Oct 11 '18 at 07:40
Difficult to know as it's all affected by the number of entries etc. But as I said, I tried it and found this to take 1/2 the time in my tests. – Nigel Ren Oct 11 '18 at 08:55

Select array values based on another array

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