ON creates event procedure calls or enables event trapping.


* Set the sub-procedure call for [[KEY(n)]], [[ON COM (n)|COM(n)]], [[PEN]], [[PLAY]], [[STRIG(n)]], [[TIMER]], [[UEVENT]]

* To turn on event trapping for [[ON COM (n)]], [[ON KEY (n)]], [[ON PEN]], [[ON PLAY (n)]], [[ON STRIG (n)]], [[ON TIMER (n)]] and [[ON UEVENT]]. 

* In the case of [[ON ERROR]] the trap is also enabled until a subsequent ON ERROR statement.
* ON procedures should be used only in the main program module and not inside of SUB procedures!
* If you have used the [[$CHECKING]]:[[OFF]] metacommand, [[$CHECKING]]:'''ON''' will turn on c++ error checking again.


''See also:'' 

[[ON...GOSUB]], [[ON...GOTO]] 

[[OFF]], [[STOP]], [[KEY]]

[[$CHECKING]]


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