Retrieve Selected Checkboxes from WebHook Submission

We have a mutual client that utilizes JotForms.  The forms contain a list of checkboxes and I am not able to capture the POSTed data.  Please point me to your documentation on where to pull this information.   The site is currently written in PHP.

Thanks!

You can do this with two different methods: 

1. WebHooks: The guide can be found here: https://www.jotform.com/help/245-How-to-Setup-a-Webhook-with-JotForm 

Here is also a link with some examples about how WebHooks can be used: https://www.jotform.com/help/248-Webhook-PHP-Script-Examples 

2. Sending POST data through the thank you page: You can use a custom thank you page and process the data there, this guide will provide you more information about it: https://www.jotform.com/help/213-Send-Submission-Data-via-Post-Method-and-Thank-You-Settings 

I hope this helps.