How to append multiple values to a single parameter in html form?

Question

Assuming I have the following form:

 Oats


        

Answer 1

More or less here the idea: first form, 1 hidden input will catch all the vaules of second and void form

 Oats
 Beans

add some fix, submit the right form. Tested on jsfiddle:

JsFiddel "working" example

ADD SINGLE FORM VERSION

You've to know the name of the field, and ignore the other params in the answer

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 Beans


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