How to reset specific form elements

Question

I have a form which I have included a reset button. Here is the code:

function submission_list($form, &$form_state) {

  ...code here...

  $form['filter']['reset'] = array(
    '#type' => 'submit',
    '#value' => t('Reset'),
    '#submit' => array('submission_list_reset'),
  );

  ... more code ...
}


function submission_list_reset($form, &$form_state) {

  if (isset($form_state['etd_filter'])) {
    unset($form_state['etd_filter']);
    $form_state['values']['filter_user'] = '';
    $form_state['input']['filter_user'] = '';
  }
  $form_state['rebuild'] = TRUE;
}

I thought what I have in the submission_list_reset function is correct but it still displays whatever the user typed in the filter_user text field. I have tried clearing the values and input array with no success so I must be missing something really basic here. I have searched Drupal Answers and Google but have not found an answer. The answers I have found on Drupal Answers is about adding a reset button but not about clearing specific fields.

Thanks.

Answer 1

You can attach the reset function in this way:

function submission_list($form, &$form_state){
  $form = array();
  $form['name'] = array(
    '#title' => 'Name',
    '#type' => 'textfield',
  );
  $form['surname'] = array(
    '#title' => 'Surname',
    '#type' => 'textfield',
  );
  $form['actions'] = array(
    '#type' => 'actions',
    'submit' => array(
      '#type' => 'submit',
      '#value' => t('Submit'),
      '#attributes' => array(
        'class' => array('my-submit-button-class')
      ),
      '#submit' => array('your_submit_function')
    ),
    'reset' => array(
      '#type' => 'submit',
      '#attributes' => array('class' => array('my-reset-button-class')),
      '#value' => t('Reset form'),
      '#submit' => array('submission_list_reset')
    )   
  );
  return $form;
}

function submission_list_reset($form, &$form_state) {
  $form_state['values']['name'] = '';
  $form_state['values']['surname'] = '';
}

function your_submit_function($form, &$form_state) {
  drupal_set_message('The form has been submitted');
}

But please consider to use ajax callback for this reset function, it would be better do not reloading the page only because of resetting. More info - Ajax forms in Drupal 7

Answer 2

Please use the right way form_set_value() in your validation function instead of $form_state['values']['surname']

Like this:

form_set_value($form['surname'], '', $form_state);

---

Update:

Please make sure to reference the $form_state and $form to the same variable in memory by making sure there is & sign before the parameters like this:

function your_submit_function(&$form, &$form_state) {