How to check if all switch objects in a room are set to true?

Question

I'm trying to implement a puzzle mechanic in Game Maker Studio 2.
Where you need to activate multiple switches for an event to happen (e.g. opening a door)

However, I'm currently stuck in recieving the booleans from all switch objects in a room.
Currently It's only working when any (or only the first) switch is hit.

Here's an example of how it works:

Switch collision with projectile:

switched = !switched

'Switchdoor' step event:

if (switch.switched == true) //this only seem te register the first switch placed
{
    //do action
}

If I've used XNA, I could make a List<> to store all the rendered switches and get their boolean values. But what can I use instead in Game Maker Studio 2, who works with rooms?

Answer 1

If my GML is not too rusty, the following should work:

var allSwitchesOn = true;

with(switch) {
    if(!switched) {
        other.allSwitchesOn = false;
        break;
    }
}

// allSwitchesOn now has the correct value