Form Field Mapping

The Form Field Mapping settings control the URL parameter names that the plugin uses when building a payment link. Each setting corresponds to one of the four client detail fields: first name, last name, email, and amount.

The Four Parameter Settings

Setting	Option Key	Default Value	Description
First Name Parameter	idplg_param_first_name	first_name	The URL parameter your form uses for the client’s first name
Last Name Parameter	idplg_param_last_name	last_name	The URL parameter your form uses for the client’s last name
Email Parameter	idplg_param_email	email	The URL parameter your form uses for the client’s email address
Amount Parameter	idplg_param_amount	amount	The URL parameter your form uses for the payment amount

How to Determine Your Parameter Names

The correct values depend entirely on your payment form. Here are examples for common form plugins:

• Gravity Forms: If you enable “Allow field to be populated dynamically” on a field and set its parameter name to fname, then set the First Name Parameter to fname.
• WPForms: WPForms uses numeric field IDs. If your first name field has ID 1, the parameter might be wpf1_1 depending on your form configuration.
• Custom HTML forms: Check your form’s JavaScript or server-side code to see which $_GET parameters it reads.

The Amount Field Is Optional

Unlike the name and email fields, the Amount field is optional in the link generator. If you leave the amount blank when generating a link, the amount parameter is omitted entirely from the URL rather than being included with an empty value. This is useful when you want the client to enter their own amount, or when the payment amount is fixed within the form itself.

URL Encoding

The plugin automatically applies urlencode() to all parameter values when building the link. This ensures that special characters in names or email addresses (such as the @ symbol or spaces) are properly encoded and do not break the URL.

Tip: After changing your parameter names, generate a test link and open it in your browser. Inspect the form fields to confirm they are pre-filled correctly with the values from the URL.