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How to avoid pre-populated data to be tampered?Asked by ssssoindia on August 23, 2016 at 10:50 AMSince you email I do have a quick question. This is how query string is
passed to JotForm:
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?
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.