If its sparking all the time then the first thing to try is turn the power off to the hob and remove the pan stands and the burner caps.
Get a hairdryer and heat the spark lead on each burner. Its the white probe as if they get wet or mositure on them it can cause it to spark all the time.
Do this on all 4 burners and then turn it back on and see if it stops it from there.
If not then its either the push switch or the spark genarator box. You need to remove the hob top panel from there to access the switch underneath and test it with a multimeter and see if there contonuity even when its not pressed. If there is then its faulty and will need to be replaced.
But if the switch is fine then the spark box will need to be replaced there to cure it.
But try the above first as drying the spark leads with a hairdryer does work alot on gas hobs.
If you need anymore info just get back to me.
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