I have 2 arrays which might look something like this:
$a1 = array('c','b','a');
$a2 = array('a', 'b', 'c', 'd', 'e');
I need to somehow check whether every value in $a1 is present in $a2.
I've looked at array_diff and array_intersect but can't see how they can be used because the only return the values that are present and not present respectively.
I am not sure what you mean by "present respectively" but array_diff is the function you are looking for. Just make sure you pass the arrays into the function in the correct order. Try:
// result = no
echo count( array_diff( $a1, $a2 ) ) ? 'yes' : 'no';
// result = yes
echo count( array_diff( $a2, $a1 ) ) ? 'yes' : 'no';
Look at this:
http://php.net/manual/de/function.in-array.php
Okay, I'll make it clearer:
The Function in_array() gives you a Boolean if the needle is in the haystack. So, a line like this will work for you:
$return = in_array($a1, $a2, true);
If $a1 is in $a2 the function returns true, otherwise false. The third Parameter activates strict search, so there won't be return even when a false would be right.
You can use something like
sizeof(array_intersect($a1, $a2)) == sizeof($a1)
function has_all_values($base, $comparing) {
foreach($comparing as $value) {
if(!in_array($base, $value))
return false;
}
return true;
}
