Passing address info from Webform to Ubercart?

No that's not currently possible. I've actually had this functionality working on a site since before the module was stable, but nobody ever requested it, so I never cleaned it up (it doesn't have a UI). I guess what we'd want is a way to map a component name to an address line in the UI. It might be a good idea to put this in a separate module (already uc_event_registration's grown larger than I'd like).

I'm very busy at the mo but should be freer in a month or so. If anyone wants to supply a patch (or make a new module) here's the code I've been using (slightly cleaned up, might need more):

/**
 * Implements hook_form_FORM_ID_alter(). Prepopulates address fields from
 * the webform (where possible).
 */
function shophelper_form_uc_cart_checkout_form_alter(&$form, &$form_state) {
  
  $cart = unserialize($form['cart_contents']['#value']);
  foreach ($cart as $product) {
    if (isset($product->data['uc_event_registration']['sid'])) {
      $sid = $product->data['uc_event_registration']['sid'];
      break;
    }
  }
  
  // Early out if there's no paidevent
  if (!isset($sid)) {
    return;
  }
  
 // The mapping still needs a prefix to be applied, eg. delivery_first_name
  $mapping = array(
    'first_name' =>         '_first_name',
    'surname' =>            '_last_name',
    'address_line_1' =>     '_street1',
    'address_line_2' =>     '_street2',
    'town' =>               '_city',
    'postcode' =>           '_postal_code',
    'telephone' =>          '_phone',
    'mobile' =>             '_phone',
  );

  // If the user only orders a paidevent then there's no delivery address as
  // there's no shipping, and so we want to fill in the billing address. If
  // there's a 'real' product in the cart as well, then we want to fill out the
  // delivery address, as there's an option to automatically populate the
  // billing address from the delivery anyway.
  
  if (isset($form['panes']['delivery'])) {
    $checkout_address =& $form['panes']['delivery'];
    foreach ($mapping as &$field_name) {
      $field_name = 'delivery' . $field_name;
    }
  }
  else {
    $checkout_address =& $form['panes']['billing'];
    foreach ($mapping as &$field_name) {
      $field_name = 'billing' . $field_name;
    }
  }
  shophelper_webform_checkout_field_mapper($checkout_address, $sid, $mapping);
  if ($form['panes']['customer']['primary_email']['#type'] === 'textfield') {
    shophelper_webform_checkout_field_mapper(
      $form['panes']['customer'],
      $sid,
      array('email' => 'primary_email')
    );
  }
}

/**
 * Populates form elements from webform submissions.
 *
 * @param &$form
 *   The form to populate. This function doesn't descend any trees to find
 *   elements.
 * @param $sid
 *   The sid of the relevant webform submission.
 * @param $mapping
 *   An array keyed by webform component form keys, with values being the
 *   corresponding form keys of $form.
 */
function shophelper_webform_checkout_field_mapper(&$form, $sid, $mapping) {
  
  $form_keys = array_keys($mapping);
  $form_key_placeholders = db_placeholders($form_keys, 'varchar');

  $sql = <<<SQL
    SELECT data, form_key
      FROM {webform_submitted_data} wsd
      JOIN {webform_component} wc
        ON
          wsd.nid = wc.nid AND
          wsd.cid = wc.cid AND
          wsd.sid = %d AND
          wc.form_key IN ($form_key_placeholders)
SQL;

  $args = array_merge(array($sid), $form_keys);

  $res = db_query($sql, $args);
  while ($record = db_fetch_array($res)) {
    $form_key = $record['form_key'];
    $element =& $form[$mapping[$form_key]];
    if (isset($element) && empty($element['#default_value'])) {
      $element['#default_value'] = $record['data'];
    }
  }

  return;
}

Glad it's of use! No worries re UI. Just wanna put the code out there; if someone codes a UI fantastic, if not no great shakes.

If you have any issues using it, do please post back here.

Thanks