Drupal Form:want to show previous form value as default_value on page

Question

My Goal is if user is submitting this form with \"Product Name\" value as \"YYY\". On submit page should reload but this time \"Product Name\" should show previous valye as

Answer 1

For anyone looking for an answer here while using webform (which I just struggled through), here's what I ended up doing:

//in hook_form_alter
$form['#submit'][] = custom_booking_form_submit;

function custom_booking_form_submit($form, &$form_state) {
//  drupal_set_message("in form submit");
//  dpm($form_state, 'form_state');

    foreach ($form_state['values']['submitted_tree'] as $form_state_key => $form_state_value) {

        $form_state['storage'][$form_state_key] = $form_state_value;
    }
}

Note: added the ' as it was lost