add to array if it isn't there already

Question

How do I add elements to an array only if they aren\'t in there already? I have the following:

$a=array();
// organize the array
foreach($array as $k=>$v)         


        

Answer 1

Try adding as key instead of value:

Adding an entry

function addEntry($entry) {
    $this->entries[$entry] = true;
}

Getting all entries

function getEntries() {
    return array_keys($this->enties);
}