You might want to take a look at the exists function. It does exactly what you're looking for: tells you if a hash key exists, regardless of what its value is. 
if(exists $input{'checkbox1'}) {

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This will work regardless of what the value of the checkbox is, as the hash key 'checkbox1' will not exist unless the checkbox is checked.

In reply to Re: How to check value of checkbox on form submit? by plaid
in thread How to check value of checkbox on form submit? by mt2k

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