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    How to accept payments for dynamic amounts.

    Asked by M Afsar on May 04, 2014 at 05:17 AM
    Hi,I am creating a form for paid research....where users will have the option to select from choices like field of research .....size......time period....etc and based on the users choices, I will calculate the total amount in total field.Now I want the user to pay the total amount generated in the total field which will be different for each user (depending on the choices), using paypal.How do I do that????? Any help in this regard?
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    JotForm Support

    Answered by TitusN on May 04, 2014 at 08:28 AM


    This can be achieved with Javascript and the forms source code

    If you created a form with the calculations you mentioned - please share it with us and we can guide on how to implement a script that can copy the calculation result to a paypal field.

    Looking forward to your response.

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    Answered by mafsar21 on May 04, 2014 at 11:40 AM


    thanks for the prompt response...(you guys are one of the fastest)..

    ok heres my form http://form.jotform.me/form/41232514064443

    As you can see after the choices are made there is a numerical value being generated in the "total cost field"..... this is the amount user will pay.........preferably with paypal standard as the payment option...

    look forward to your response.. 

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    JotForm Support

    Answered by BDAVID on May 04, 2014 at 01:08 PM

    Hi, I you can implement this by following this steps: 

    1)  Hide the Total Cost fields, click on the gear icon and click on  "Hide Field", this just serve as our based field for the Paypal field:

    2) Get your form source codes: How to Get Form Source Codes and save it as an HTML file. You will have to host this HTML file to your own server because there's no way you can import the modified source codes to our form builder.

    3) Add the following script to the source codes: http://pastiebin.com/53321e8a9ddd4. Add this to the bottom, after the end tag:

    You'll notice the ID: input_93_donation. This is different from your Paypal input field ID, so you have to change this. You can find the ID of the field by following this guide: How to Find Field IDs & Names..

    4) You have to add this event script to the Total Cost: http://pastiebin.com/533220f79d2e5, add this to the input properties of the Total Cost field:

    5) That would be it,  save the changes and upload it to your server.  

    Hope this helps you, let us know what happens, we will be glad to assist you.

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    Answered by mafsar21 on May 04, 2014 at 09:17 PM

    GREAT! Thanks a lot!

    You guys are amazing! Working perfectly fine

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    JotForm Support

    Answered by ashwin_d on May 05, 2014 at 12:03 AM

    Hello mafsar21,

    On behalf of my colleagues, you are welcome.

    Do get back to us if you have any questions.

    Thank you!