gform_paypal_query

Description

Use this filter to modify the query string that will be sent to PayPal. This filter is fired immediately before the user is redirected to PayPal.

Usage

add_filter( 'gform_paypal_query', 'your_function_name', 10, 5 );

Examples

Modify Pricing

This example demonstrates how to remove negative prices from the query string (which are would otherwise generate an error with PayPal) and to subtract that value from the highest priced item.

add_filter( 'gform_paypal_query', 'update_paypal_query', 10, 3 );
function update_paypal_query( $query_string, $form, $entry ) {

    parse_str( $query_string, $query );

    $id = 0;
    $amounts = array();

    foreach ( $query as $key => $value ) {

        if ( (int) $value >= 0 ) {
            $amounts[] = $value;
            continue;
        } else {
            $id = str_replace( 'amount_', '*', $key );
            $discount = abs( $value );
        }

    }

    if ( $id ) {
        unset( $query['item_name_' . $id] );
        unset( $query['amount_' . $id] );
        unset( $query['quantity_' . $id] );
    }

    foreach ( $query as $key => &$value ) {
        if ( strpos( $key, 'amount_' ) !== false ) {
            $value = $value - $discount;
        }
    }

    $query_string = http_build_query( $query, '', '&' );

    return '&' . $query_string;
}

Disable Tax

This example shows how you can disable tax:

add_filter( 'gform_paypal_query', 'update_paypal_query', 10, 3 );
function update_paypal_query( $query_string, $form, $entry ) {

	$my_forms = array( 1, 5, 7, 9, 276 ); // list of form id's to apply this separated by comma

	// skip processing if the form id is not in the array of forms id's
	if ( !in_array( $form['id'], $my_forms ) ) {
		return $query_string;
        }

	// apply only if form ID is 1
	parse_str( $query_string, $query );
	$query['tax_1'] = '0.00';
	$query['tax_2'] = '0.00';
	$query['tax_3'] = '0.00';
	$query['tax_4'] = '0.00';
	$query['tax_5'] = '0.00';
	$query['tax'] = '0.00';
	$query_string = http_build_query( $query, '', '&' );
	return '&' . $query_string;
}

Set the Language Code

This example shows how you can set the language code. You can find the full list of language codes in PayPal’s developer documentation.

add_filter( 'gform_paypal_query', 'update_paypal_query', 10, 3 );
function update_paypal_query( $query_string, $form, $entry ) {
	if ( $form['id'] == 323 ) {
		$query_string .= '&lc=en_GB';
	} else {
		$query_string .= '&lc=en_US';
	}

	return $query_string;
}

And your Logo to Checkout page

This example shows how you can set the image URL to display your logo in PayPal’s checkout page.

add_filter( 'gform_paypal_query', 'add_image_url', 10, 3 );
function add_image_url( $query_string, $form, $entry ) {
	// Update 1 to your form id. Remove the if statement if you want to add the image to all forms.
    if ( $form['id'] == 1 ) { 
        $query_string .= '&image_url=https://example.com/some/path/image.png'; // Size of the image must be 150 x 150 pixels
    }
 
    return $query_string;
}

Add Invoice number

This example shows how you can populate the invoice parameter with a value from a field in your form.

add_filter( 'gform_paypal_query', 'add_invoice_number', 10, 3 );
function add_invoice_number( $query_string, $form, $entry ) {
	// Update 1 with the id number for the field that contains your invoice number
	$invoice_number = rgar( $entry, '1' );

	// Update 323 with your form id
    if ( $form['id'] == 323 ) {
        $query_string .= '&invoice=' . $invoice_number;
    }
 
    return $query_string;
}

Set the landing page

See this gist from WebAware.

Placement

This code should be placed in the functions.php file of your active theme.

Source Code

gf_apply_filters( 'gform_paypal_query', $form['id'], $query_string, $form, $entry, $feed, $submission_data )

This filter is located in GFPayPal::redirect_url() in class-gf-paypal.php.