Using Gravity Forms ‘gform_preview_header’ PHP filter

by

The gform_preview_header action is triggered when the header of the form preview page loads, allowing further actions to be done.

Usage

add_action('gform_preview_header', 'my_custom_function', 10, 1);

Parameters

  • $form_id (int): The ID of the current form being previewed.

More information

See Gravity Forms Docs: gform_preview_header

This action hook was added in Gravity Forms 2.4.19.

Source Code: This action hook is located in preview.php.

Examples

Add custom CSS to form preview header

This example adds custom CSS to the form preview header.

function my_custom_function($form_id) {
    echo '<style>
            body { background-color: #f9f9f9; }
            .gform_wrapper { border: 1px solid #ccc; }
          </style>';
}
add_action('gform_preview_header', 'my_custom_function', 10, 1);

Display a custom message above the form

This example displays a custom message above the form in the form preview.

function my_custom_function($form_id) {
    echo '<div class="custom-message">This is a form preview. Some features might not work as expected.</div>';
}
add_action('gform_preview_header', 'my_custom_function', 10, 1);

Load a custom JavaScript file

This example loads a custom JavaScript file in the form preview header.

function my_custom_function($form_id) {
    echo '<script src="/path/to/your/custom.js"></script>';
}
add_action('gform_preview_header', 'my_custom_function', 10, 1);

Add custom meta tags to form preview header

This example adds custom meta tags to the form preview header.

function my_custom_function($form_id) {
    echo '<meta name="viewport" content="width=device-width, initial-scale=1">';
}
add_action('gform_preview_header', 'my_custom_function', 10, 1);

Conditionally load custom styles for specific forms

This example loads custom styles for specific forms based on their form ID.

function my_custom_function($form_id) {
    if ($form_id == 5) {
        echo '<style>
                body { background-color: #f9f9f9; }
                .gform_wrapper { border: 1px solid #ccc; }
              </style>';
    }
}
add_action('gform_preview_header', 'my_custom_function', 10, 1);