Handling nested formular data


it’ll be my job to create formulars where the given information can be
strutured. There’s not only value1=x, value2=y, value3=z, but also
value1=x, value1_a=y, value1_b=z and so on. I’m asking myself whether
it’s good to save those meta informationen in the formular data anyhow
or to have a kind of parser, which structures the information given by
the formular data on the basis of a predefined syntax definition and
validates the incoming data with a state machine, for example. The
problem is, I think, that a formular can easily be manipulated and
thus an extra checking is necessary anyhow.

Thank you for any suggestions!