OnTriggerStay called once option?

so I am using a trigger collider. I don't wanna know every frame if the other collider is in the Trigger, I just want to call it once like in a for statement. like this:

var allothers = all colliders inside this trigger;
for (var other : Collider in allothers) 

of course thats not real but is there a way to do that? I'm trying to stay away from Ontriggerstay because I don't need to know all the colliders in the trigger each frame - I just need to check once or twice.