PHP equal variables

Question

I wondered if there is any way to check if any of a large amount of variables are equal. If I only have a few variables I can just do this:

if ($a == $b || $a == $c || $b == $c)

However, if I have 20 variables it will take some time to write all combinations. Is there another method?

Answer 1

if (count(array_unique(array($a, $b, $c), SORT_REGULAR)) === 1) {
    // all equal
}

All this code does is place the variables in an array and eliminates duplicates. If they are all equal the result of array_unique() should be an array with one value.

If you want to make sure all of them are different it's not much different. Just check to see if the filtered array is the same size as the original array:

$array = array($a, $b, $c);
if (count(array_unique($array, SORT_REGULAR)) === count($array)) {
    // all not equal 
}