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    Validation - Alphanumeric but can't start with a number?

    Asked by rebirthdesign on February 27, 2014 at 03:10 AM

    Hi there!

    I'm wondering what kinds of additional tricks can be applied to the validation that can be applied to text boxes etc?  Presently it can be none; alpha; alphanumeric; numeric; or email.

    How can I have alphanumeric but NOT say allow user to start their input with a number?


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    JotForm Support

    Answered by ashwin_d on February 27, 2014 at 08:59 AM

    Hello rebirthdesign,

    This can be only achieved by adding custom regular expression or you can download your form's source code and add custom javascript to validate the user input.

    Do get back to us if you like to take the source code route and we will try to give you a custom JavaScript code to achieve your requirement.

    There is actually one other option which is very close to your requirement. You you know / have the format of the input text, you can actually use our "Input Mask" property of "Text Box" field. Please check the screenshot below:

    Please check this demo form I created for you:  http://www.jotformpro.com/form/40573241260950  In this, I have added an input max for 10 character but the first characted cannot be a number. Please be noted that while setting up input max, you should use @ symbol to mask letters inputs, # for numbers and * for both.

    Feel free to clone this form for a closer look. The following guide should help you in form cloning:  https://www.jotform.com/help/42-How-to-Clone-an-Existing-Form-from-a-URL

    Hope this helps. Do get back to us if you have any questions.

    Thank you!

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    Answered by rebirthdesign on February 27, 2014 at 01:15 PM


    Thanks - this works great on text box field - what about email fields?  I don't see the input mask property.  Perhaps I'll have to go the js route?

    Thanks to please advise!


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    JotForm Support

    Answered by Welvin on February 27, 2014 at 03:25 PM


    Input Masking is not enabled into our Email Field. Yes, I think that the only way is to use our source codes and apply a custom validation.

    We'll see if we can come up for an example.