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    How to avoid pre-populated data to be tampered?

    Asked by ssssoindia on August 23, 2016 at 10:50 AM
    Since you email I do have a quick question. This is how query string is
    passed to JotForm:
    ?x=10&y=20&lock=6d2efc914e42ec1eb8594273407ee9f039d72be5
    Where lock is secure hash of the query string params and I need to validate
    params x and y are not tampered before posting. Is there any way we could
    that kind of validation?
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    JotForm Support

    Answered by Kevin_G on August 23, 2016 at 11:07 AM

    This will be achieved with conditions, if you have the value for "X" and "Y" predefined.

    First you need to add the message to indicate your users that the value cannot be changed: 

    Now set up the condition:

    Now even if the value is changed on the link then the message will be shown. 

    Here is a guide that will also help you with showing or hiding fields with conditions: How-to-Show-or-Hide-Fields-Base-on-User-s-Answer

    Here is also my form so you can test: https://form.jotform.com/62353959497978?x=10&y=20 

    Feel free to clone my form How-to-clone-an-existing-form-from-a-URL

    Hope this helps.