PHP array delete by value (not key)

I have a PHP array as follows:

$messages = [312, 401, 1599, 3, ...];

I want to delete the element containing the value $del_val (for example, $del_val=401), but I don't know its key. This might help: each value can only be there once.

I'm looking for the simplest function to perform this task, please.

Answer

Using array_search() and unset, try the following:

if (($key = array_search($del_val, $messages)) !== false) {
    unset($messages[$key]);
}

array_search() returns the key of the element it finds, which can be used to remove that element from the original array using unset(). It will return FALSE on failure, however it can return a false-y value on success (your key may be 0 for example), which is why the strict comparison !== operator is used.

The if() statement will check whether array_search() returned a value, and will only perform an action if it did.