Question

我正在使用Drupal7，因为我有模块，其中我已经使用php编写了我自己的函数，其中有两个下拉列表，现在我的要求是当我选择例如说＆＃34; A＆＃34;从第一次下降到第二次下降只与＃34; A＆＃34;所有数据都需要在第二个下拉菜单中显示简单来说，如果我从第一个下拉列表中选择城市名称，那么该城市的所有大学都应该显示在第二个下拉列表中。我如何在PHP中实现这一点？我发现了这个链接和一段代码http://w3shaman.com/article/creating-ajax-dropdown-drupal-7但是没有使用，如果有人为此做出回应，对我来说会很有帮助。

Answer 1

如果您使用Drupal Form API创建表单，那么您可以使用Drupal Ajax实现此目的。下面是Drupal Ajax示例模块的代码片段

function ajax_example_dependent_dropdown($form, &$form_state) {
  // Get the list of options to populate the first dropdown.
  $options_first = _ajax_example_get_first_dropdown_options();
  // If we have a value for the first dropdown from $form_state['values'] we use
  // this both as the default value for the first dropdown and also as a
  // parameter to pass to the function that retrieves the options for the
  // second dropdown.
  $selected = isset($form_state['values']['dropdown_first']) ? $form_state['values']['dropdown_first'] : key($options_first);
  $form['dropdown_first'] = array(
    '#type' => 'select',
    '#title' => 'Instrument Type',
    '#options' => $options_first,
    '#default_value' => $selected,
    // Bind an ajax callback to the change event (which is the default for the
    // select form type) of the first dropdown. It will replace the second
    // dropdown when rebuilt.
    '#ajax' => array(
      // When 'event' occurs, Drupal will perform an ajax request in the
      // background. Usually the default value is sufficient (eg. change for
      // select elements), but valid values include any jQuery event,
      // most notably 'mousedown', 'blur', and 'submit'.
      // 'event' => 'change',
      'callback' => 'ajax_example_dependent_dropdown_callback',
      'wrapper' => 'dropdown-second-replace',
    ),
  );

  $form['dropdown_second'] = array(
    '#type' => 'select',
    '#title' => $options_first[$selected] . ' ' . t('Instruments'),
    // The entire enclosing div created here gets replaced when dropdown_first
    // is changed.
    '#prefix' => '<div id="dropdown-second-replace">',
    '#suffix' => '</div>',
    // When the form is rebuilt during ajax processing, the $selected variable
    // will now have the new value and so the options will change.
    '#options' => _ajax_example_get_second_dropdown_options($selected),
    '#default_value' => isset($form_state['values']['dropdown_second']) ? $form_state['values']['dropdown_second'] : '',
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}    

function ajax_example_dependent_dropdown_callback($form, $form_state) {
  return $form['dropdown_second'];
}

function _ajax_example_get_second_dropdown_options($key = '') {
  $options = array(
    t('String') => drupal_map_assoc(
    array(
      t('Violin'),
      t('Viola'),
      t('Cello'),
      t('Double Bass'),
    )
    ),
    t('Woodwind') => drupal_map_assoc(
    array(
      t('Flute'),
      t('Clarinet'),
      t('Oboe'),
      t('Bassoon'),
    )
    ),
    t('Brass') => drupal_map_assoc(
    array(
      t('Trumpet'),
      t('Trombone'),
      t('French Horn'),
      t('Euphonium'),
    )
    ),
    t('Percussion') => drupal_map_assoc(
    array(
      t('Bass Drum'),
      t('Timpani'),
      t('Snare Drum'),
      t('Tambourine'),
    )
    ),
  );
  if (isset($options[$key])) {
    return $options[$key];
  }
  else {
    return array();
  }
}

如何通过从相应的下拉列表中选择特定数据来显示下拉列表中的相关数据

1 个答案: