无法获取要在页面上显示的json请求。用户需要选择一个值并发送给请求

Question

我目前正在开发一个webisite，要求用户从列表中选择黄金或白银，然后将其传递给JS文件，然后发出API请求以显示所选金属的当前值。结果应显示在屏幕上，而无需重新加载整个页面。问题是当我加载页面时根本没有发生任何事情。页面应该在加载时显示银的默认值。任何帮助将不胜感激。

(function($) {
    // var apiKey = '348e90c9b0fdb12a5e5ca407328ffdae';
    // var apiURI = 'http://apilayer.net/api';

    // set endpoint and your access key

    endpoint = 'live'
    access_key = '348e90c9b0fdb12a5e5ca407328ffdae';

    //code the quote function 
    function quote() {
      //set variable for use in the JSON request.
      var type = $('#type').val(),
        //add USD to the end of the variable string, since format had the first 3 letters as the base for converting
        type = type + 'USD',

        // get the most recent exchange rates via the "live" endpoint:
        $.ajax({
            url: 'http://apilayer.net/api/' + endpoint + '?access_key=' + access_key,
            dataType: 'jsonp',
            success: function(json) {

              // exchange rata data is stored in json.quotes
              alert(json.quotes.(type);

                // source currency is stored in json.source
                alert(json.source);

                // timestamp can be accessed in json.timestamp
                alert(json.timestamp);

              }
            });

          complete: function(req, textStatus) {

            switch (req.status) {

              case 404:
                showError('User requested a resource which does not exist!');
                break;
              case 101:
                showError('User did not supply am access key!');
                break;
              case 103:
                showError('User requested a non-existent API function!');
                break;
              case 104:
                showError('User has reached or exceeded their plan monthly API reqquest allowance');
                break;
              case 105:
                showError('User subscription does not support API Function');
                break;
              case 106:
                showError('User Query did not find any results');
                break;

              default:
                break;
            }
          }
        });
  }
  // event handler for when the convert button is selected
  // event handler: document is ready/finished loading
  $(document).ready(function() {

    // event handler: form submit
    $('form').submit(function(e) {
      // prevent form submission
      e.preventDefault();
    });

    // event handler: search button click
    $('#quote').click(function(e) {
      search();
    });

    search();
  });
})(jQuery);

<link rel="stylesheet" href="style.css">
<script src="https://unpkg.com/popper.js/dist/umd/popper.min.js"></script>
<!-- jquery js file from JQuery.com -->
<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
<!-- script to run Coin function-->
<script src="coin.js"></script>

<header>
  <h1>Silver & Gold Value</h1>
</header>
<!-- Introduction to the purpose of the program-->
<h2>Purpose</h3>
  I am a big coin collector, and go to a lot of auctions. And most of the coins i purchase are made of either gold or Silver. A lot of time the only value a coin had is the amount of gold or silver the coin contains. This is whats know as a "Junk Coin".
  This page hopes to help in knowing the current value of both gold and silver so that if you are ever at an auction or need to know the current value of a coin, the information is readily available.
  <h2>Find Value</h2>
  Select either gold or silver from the list to find its up-to-date value.
  <!-- create a form that holds the list of the 2 metal options-->
  <Form id="metal">
    <div class="form-group">
      <label class="currencies" for="type">Select a Metal:</label>
      <select class="form-control" id="type" name="type">
        <option value='XAG' title='Silver (troy ounce)'>Sliver</option>
        <option value='XAU' title='Gold (troy ounce)'>Gold</option>
      </select>
    </div>
    <button type="button" class="btn btn-primary type currencies" id="quote">Convert</button>
  </form>


  <h2>Results</h2>

  <div id="results" class="d-flex flex-wrap justify-content-center"></div>
  </main>

任何帮助将不胜感激。谢谢大家