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    How can I have a hash of the submitter's IP address included as a hidden field?

    Asked by verifine on November 05, 2012 at 06:50 AM

    I'm building a "suggestion box" for our college, which promises the user that submissions are confidential unless they also submit their Email address or phone number.  Users on campus only may submit forms, at a local URL which has the jotform script embedded.  What I want to do is have the HTML page redirect to a CGI script (which I'll write) that will send the user's browser to Jotform to fill out the form, but will also include a hash of the user's IP address as a hidden field.

    I don't want to know who is submitting forms, but by using an MD5 hash, if the same IP address submits more than one form, the hash will be identical.  Just a small tool for us to help in dealing with "ballot stuffing," while preserving the submitter's anonymity.

    Excellent service, and I intend to push the college to subscribe to your service.

    Curt Lundgren, Network Administrator, Watkins College of Art, Design & Film, Nashville TN

    Page URL:

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    JotForm Support

    Answered by liyam on November 05, 2012 at 07:57 AM

    Thank you for your kind remark, Curt.

    I'm not sure how you would wish to do this, but the simpliest solution I could think of for your case is that:

    1. Edit your form via the form builder (in JotForm) and add the hidden text field.

    2. Get the HTML source of your form (You can read on this user guide how).

    3. Place the HTML source on your page (which will run your CGI script) and then modify the value of the hidden field on your form.

    This way, you can fully modify the functionalities of your form.  Including that of your page to capture the IP address of the form user before he makes a submission.

    If there is something I'm not understanding properly, please let us know.



  • Profile Image

    Answered by verifine on November 05, 2012 at 11:45 AM

    I've gotten the hidden field to work.  I did have to change paths to CSS and Javascript directories and haven't gotten the denim background to work outside the form (it's present inside the form.)  I appreciate the help and the hint.

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    JotForm Support

    Answered by liyam on November 05, 2012 at 12:17 PM

    We're glad to know that you have found yourself a solution, verifine.

    If you have other questions or concerns. just let us know.