使用jquery hide / show删除html

In the option (HTML) menu added "Other". if the article isn't listed returns a another input using jquery, but it does not send the $_POST only for and work for

VAR_DUMP POST ::

["link"]=> string(0) "" 

CODE (MVC - CODEIGNITER) ::

    <div class="form-group">  
      <label class="col-md-4 control-label" for="assign_article">Assign Article to Menu</label>
      <div class="col-md-4">
        <select name="link" class="form-control">
      <?php 
           foreach($get_data as $ShowMenu) { ?>
               <option value="<?php echo $ShowMenu['id']; ?>"><?php  echo $ShowMenu['title']; ?></option>

        <?php } ?>
        <option value="parent">Other</option>
        </select>
      </div>
          </div>
  <!-- Text input-->
    <div id="parentPermission" class="form-group">
      <label class="col-md-4 control-label" for="menu_name">Other:</label>
      <div id="parentPermission" class="col-md-4">
        <input id="parentPermission" name="link" type="text" placeholder="menu name" class="form-control input-md">
        </div>
    </div>
       <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js">    </script>
<script>
    $(document).ready(function () {
        toggleFields(); //call this first so we start out with the correct visibility depending on the selected form values
        //this will call our toggleFields function every time the selection value of our underAge field changes

    $("#link").change(function () {
        toggleFields();
    });
});

//this toggles the visibility of our parent permission fields depending on the current selected value of the underAge field

function toggleFields() {

    if ($("#link").val() == 'parent')

        $("#parentPermission").show();
    else
        $("#parentPermission").hide();
} 
</script>
    <!-- Select Basic -->
    <div class="form-group">
      <label class="col-md-4 control-label" for="assign_article">Add as</label>
      <div class="col-md-4">
        <select id="status" name="status" class="form-control">
          <option value="1">Parent</option>
          <option value="0">Child</option>
        </select>
      </div>
    </div>

HTML RENDERED ::

<div class="form-group">
      <label class="col-md-4 control-label" for="assign_article">Assign Article to Menu</label>
      <div class="col-md-4">
          <select name="link" id="link" class="form-control">
              <option value="89">page title</option>
              <option value="parent">Other</option>
          </select>
      </div>
    </div>
  <!-- Text input-->

    <div id="parentPermission" class="form-group">
      <label class="col-md-4 control-label" for="menu_name">Other:</label>
      <div id="parentPermission" class="col-md-4">
        <input id="parentPermission" name="link2" type="text" placeholder="menu name" class="form-control input-md">
        </div>
    </div>