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Sure, you could use a micro switch, or a spring arm limit switch. web page



I once wired up an alarm using a micro switch. It was done in such a way that when the door was opened, the alarm sounded. Inside the garage was an isolating switch (an ordinary light switch) which only the people who should know, knew where it was located.

It meant that the alarm sounded even when authorised people went in until they switched it off, and it sounded again when they switched it on again on the way out, until the door was closed, but that was the way the company whose garage it was wanted.
However, it should be easy enough to adapt to your needs

The good thing about it was that micro switches are a lot less temperamental than motion sensors

Too old to die young, too ugly to leave a good looking corpse