Gravity Form Button Customisation

gistfile1.txt

// filter the Gravity Forms button type
add_filter('gform_submit_button', __NAMESPACE__ . '\\form_submit_button', 10, 2);

function form_submit_button($button, $form)
{
    // Add custom classes to your button
    $classes = 'btn1 form-submit-btn';

    // Replace default input tag with button opening tag
    $button = str_replace('<input', '<button', $button);

    // Replace default closing input tag with button closing tag
    $button = str_replace('/>', '></button>', $button);

    // Outputs clasess on button tag 
    $button = str_replace("class='", "class='" . $classes . " ", $button);

    // Preg_match gets an array of regex matches to the 3rd param
    preg_match("/value='([^\']*)'/", $button, $value);
    
    // Adds span tags to all buttons by default and outputs value set via admin form control
    $button = str_replace('></', '><span>' . $value[1] . '</span></', $button);

    return $button;
}