Okay, makes sense.  My goal in this case is to take care of some field data validation before allowing the submission.  What's the common way people achieve this?

First, is there a reason the built in validation isn't an option?

You actually have a couple options.

1. Create your own submit button, hide the default one. Then, when the user clicks your button run the validation, and if it passes, trigger the click on the built-in submit button
2. Use JavaScript to add a custom parsley validator, which will work with the built-in processes and prevent submission if validation fails.

All the recent versions of Forms use Parsley Validation, which makes it very easy to add your own custom validation to get all the "bells and whistles" like flagging the field as in red and preventing submission.

Parsley is a common tool that's not exclusive to Laserfiche, so there's a lot of documentation you can reference.

Okay, cool.  I'll look into Parsley.  In this case, I have 2 time fields representing a start and end time.  I'm converting them to military time to verify that the start time is before the end time, so there are essentially 4 fields worth of data that need to be complete before doing the validation, startTime, startTimeAMPM, endTime, endTimeAMPM. 

That's definitely something you can do with Parsley. I've done similar things to make sure "start dates" are less than "end dates" on some forms in the past.

If you wanted to get super fancy, you can actually use JavaScript to dynamically update the min/max values for the fields based on the inputs; this would give you similar validation, but it is a bit more complicated.