减去数组以获得每个差异

Question

What I have

$array1 = [1,1,1];
$array2 = [1,1];

What I'm doing:

array_diff( $array1, $array2 );

What I expected:

array(1) { 1 }

What I got

array(0) { }

How do I subtract two arrays to get every discrepancy?

---

Edit: My example was incomplete, sorry.

If we also have values like this:

$array1 = [1,1,2,1];
$array2 = [1,1,1,2];

I would expect

[1,1,2,1] - [1,1,1,2] = []

Answer 1

array_diff_assoc() is the right way to go here. But to get your expected result you just have to sort the array first with usort() where I compare the values with strcasecmp().

So this should work for you:

<?php

    $array1 = [1,1,2,1];
    $array2 = [1,1,1,2];

    function caseCmpSort($a, $b){
        return strcasecmp($a, $b);  
    }

    usort($array1, "caseCmpSort");
    usort($array2, "caseCmpSort");

    $result = array_diff_assoc($array1, $array2);

    print_r($result);

?>

output:

Array ( )