Check if 2 vars are not in array in php - php

Question

This is one is confusing me.
I am trying to check if 2 vars are not in an array with an OR, but it returns the opposite results than the expected.
Does 2 !in_array, in conjunction with an OR, creates 2 negatives = positive?
The case:
$user->groups = array(2,13,15);
if ( !in_array(2, $user->groups) || !in_array(0, $user->groups) ) {
echo "Not in Array";
} else {
echo "In Array";
}
Since 2 is in the array, I expect the script to echo "In Array", but it echoes "Not in Array". If I remove the second !in_array after the OR, it echoes "In Array". If I change the OR with an AND, it echoes "In Array".
It doesn't make much sense, or I am just that confused at the moment. Can someone give some input?

Answer 1

The problem is you are using || instead of &&. What the logical OR (||) does is that it checks the first condition and if it is true then it does not test the other conditions in the if statement. Here is the revised code:
$user->groups = array(2,13,15);
if ( !in_array(2, $user->groups) && !in_array(0, $user->groups) ) {
echo "Not in Array";
} else {
echo "In Array";
}
Hope this helps!

Answer 2

Try this:
if ( !in_array(2, $user->groups) && !in_array(0, $user->groups) ) {
echo "Not in Array";
} else {
echo "In Array";
}
This will ensure that when both (&&) 0 and 2 are not in the array, it prints "Not in array"

Answer 3

As stated in my comment, you should be checking that the first value and the second value are not in the array: !in_array(2, $user->groups) && !in_array(0, $user->groups).
For two conditions, I would consider the following suggestion overkill but you may find it useful if you want to search for a larger number of values:
$arr = array(1,2,3);
$search = array(1,2);
$all_in = function($prev, $curr) use ($arr) {
return $prev && in_array($curr, $arr);
};
if (array_reduce($search, $all_in, true)) {
echo 'all values in $search are in $arr';
}
else {
echo 'some of the values in $search are not in $arr';
}
array_reduce applies the callback function $all_in to each of the values of the $search array and keeps track of a boolean value (initialised to true) that remains true as long as all the values are in the array $arr.
As I said, this approach isn't particularly useful if you're only looking for two values but one benefit is that you can easily add values to the $search array without changing any of the other code.