Form Entry Secure Verification

The idea of my form is to collect data from exhibitors. But I don't want a random person finding the form online, and submitting some fake data.

Is the anyway of having some kind of verification code (preset by me), that they have to enter, before the form is allowed to be submitted. Like a password key that allows the person filling in the form, to successfully submit the data.

Is there a trick I'm missing. Any suggestions would be great but if this is something that is not supported in gravity forms then no worries.

Even better though, how about an array or list of entry verification variables. Now that would be cool. If you need me to elaborate at all on the above then please let me know.

Thanks in advance

Hi David, Thanks for getting back to me.

I'm very basic with code like this, so maybe its just a bit to complex for me. I've read the documentation a couple of time and don't quite get it.

I've copied and pasted the code into my themes functions. I use the functions.php quite often so I'm sure I've pasted it in correctly (excluding the php tags and line numbers).

I've changed the top line 'add-filter' gform_validation_9 to gform_validation_2 because my form I want custom validation on is form ID 2.

Now I'm stumped, I've given the class 'validate-vin' to a single line text field in my ID 2 form and the form completes with-out asking me for a vin validation. I don't really understand how else I'm meant link it to work with my form. Is something automatically meant to pop up in the form editor once this function is implemented?

Do you know of any simple validation hook demos and files out there that I could use. This looks like what I need but nothing seems to happen when I put it in.

Thanks in advance

Yeah this is totally understandable. Thanks for your help.

Definitely something you should think of building into your system thought, a validation key system of sorts. So many possibility's.