Modify form data after submit

Just so i'm clear, do you want to save the path to that PNG file as the value of the value of the upload field the user used to upload the eps or ai file? Or do you want to store the path to the PNG as the value of a different field on the form, which could be a hidden field. Either way you'd have to store the value in an existing field. Which route were you wanting to take?

If you want to update the value of the hidden field with the path to the PNG file that was generated, you would simply update the value of the hidden field that you have added to your form to store this data as part of your custom code that is executed using the gform_after_submission hook.

After you process the uploaded file and generate the PNG file, you would then update the value of the hidden field via it's field id using the entry object.

Here is documentation for the gform_after_submission hook:

http://www.gravityhelp.com/documentation/page/Gform_after_submission

Here is documentation for the entry object itself:

http://www.gravityhelp.com/documentation/page/Entry_Object

We don't have an API for that, so you will have to manually insert the value in the wp_rg_lead_detail table. Assuming your hidden field is submitted blank, the following should do the trick:

global $wpdb;
$wpdb->insert("wp_rg_lead_detail", array("value" => $url, "lead_id" => $entry["id"], "field_number" => $hidden_field_id));

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