本篇文章为大家opencart讲解购物车的一个功能优化，这个功能的优化很多客户都说用户体验非常好，下面让我们直入主题。

使用过opencart3.0版本的程序，我们都知道它这个购物车页面 在更新或者删除单个商品的时候刷新整个网页，虽然对购物流程没有什么影响，但是如果

购物车商品很多，那么用户在改个数量或者删除的时候，页面反复刷新，客户也需要从新再去找到需要修改的商品，这个过程就有些复杂了。

下面我们通过修改程序，让这个页面不全部更新，这样用户也不用反复的去查找商品了。  点击查看测试demo

下面代码是路径catalog\view\theme\default\template\checkout\cart.twig 我修改后的代码，由于这里修改讲解较为复杂，所以大家可以比对一下原来的

文件和我这个文件有代码不一样的地方。 这里给大家提供一个代码对比的网站工具。

{{ header }}
<div id="checkout-cart" class="container">
  <ul class="breadcrumb">
    {% for breadcrumb in breadcrumbs %}
    <li><a href="{{ breadcrumb.href }}">{{ breadcrumb.text }}</a></li>
    {% endfor %}
  </ul>
  {% if attention %}
  <div class="alert alert-info"><i class="fa fa-info-circle"></i> {{ attention }}
    <button type="button" class="close" data-dismiss="alert">&times;</button>
  </div>
  {% endif %}
  {% if success %}
  <div class="alert alert-success alert-dismissible"><i class="fa fa-check-circle"></i> {{ success }}
    <button type="button" class="close" data-dismiss="alert">&times;</button>
  </div>
  {% endif %}
  {% if error_warning %}
  <div class="alert alert-danger alert-dismissible"><i class="fa fa-exclamation-circle"></i> {{ error_warning }}
    <button type="button" class="close" data-dismiss="alert">&times;</button>
  </div>
  {% endif %}
  <div class="row">{{ column_left }}
    {% if column_left and column_right %}
    {% set class = 'col-sm-6' %}
    {% elseif column_left or column_right %}
    {% set class = 'col-sm-9' %}
    {% else %}
    {% set class = 'col-sm-12' %}
    {% endif %}
    <div id="content" class="{{ class }}">{{ content_top }}
      <h1>{{ heading_title }}
        {% if weight %}
        &nbsp;({{ weight }})
        {% endif %} </h1>

        <div class="table-responsive">
          <table class="table table-bordered">
            <thead>
              <tr>
                <td class="text-center">{{ column_image }}</td>
                <td class="text-left">{{ column_name }}</td>
                <td class="text-left">{{ column_model }}</td>
                <td class="text-left">{{ column_quantity }}</td>
                <td class="text-right">{{ column_price }}</td>
                <td class="text-right">{{ column_total }}</td>
              </tr>
            </thead>
            <tbody>
            
            {% for product in products %}
            <tr class="product-thumb">
              <td class="text-center">{% if product.thumb %} <a href="{{ product.href }}"><img src="{{ product.thumb }}" alt="{{ product.name }}" title="{{ product.name }}" class="img-thumbnail" /></a> {% endif %}</td>
              <td class="text-left"><a href="{{ product.href }}">{{ product.name }}</a> {% if not product.stock %} <span class="text-danger">***</span> {% endif %}
                {% if product.option %}
                {% for option in product.option %} <br />
                <small>{{ option.name }}: {{ option.value }}</small> {% endfor %}
                {% endif %}
                {% if product.reward %} <br />
                <small>{{ product.reward }}</small> {% endif %}
                {% if product.recurring %} <br />
                <span class="label label-info">{{ text_recurring_item }}</span> <small>{{ product.recurring }}</small> {% endif %}</td>
              <td class="text-left">{{ product.model }}</td>
              <td class="text-left"><div class="input-group btn-block" style="max-width: 200px;">
                  <input type="text" name="quantity[{{ product.cart_id }}]" value="{{ product.quantity }}" size="1" class="form-control" />
                  <div class="input-group-btn">
                  <button type="button" data-toggle="tooltip" title="{{ button_update }}" class="btn btn-primary update-cart"><i class="fa fa-refresh"></i></button>
                  <button type="button" data-toggle="tooltip" title="{{ button_remove }}" data-cart-id="{{ product.cart_id }}" class="btn btn-danger remove-cart"><i class="fa fa-times-circle"></i></button>
                  </div></div></td>
              <td class="text-right">{{ product.price }}</td>
              <td class="text-right">{{ product.total }}</td>
            </tr>
            {% endfor %}
            {% for voucher in vouchers %}
            <tr>
              <td></td>
              <td class="text-left">{{ voucher.description }}</td>
              <td class="text-left"></td>
              <td class="text-left"><div class="input-group btn-block" style="max-width: 200px;">
                  <input type="text" name="" value="1" size="1" disabled="disabled" class="form-control" />
                  <div class="input-group-btn">
                  <button type="button" data-toggle="tooltip" title="{{ button_remove }}" class="btn btn-danger" onclick="voucher.remove('{{ voucher.key }}');"><i class="fa fa-times-circle"></i></button>
                  </div></div></td>
              <td class="text-right">{{ voucher.amount }}</td>
              <td class="text-right">{{ voucher.amount }}</td>
            </tr>
            {% endfor %}
              </tbody>
            
          </table>
        </div>
      {% if modules %}
      <h2>{{ text_next }}</h2>
      <p>{{ text_next_choice }}</p>
      <div class="panel-group" id="accordion"> {% for module in modules %}
        {{ module }}
        {% endfor %} </div>
      {% endif %} <br />
      <div class="row">
        <div class="col-sm-4 col-sm-offset-8">
          <table class="table table-bordered total-table">
            {% for total in totals %}
            <tr>
              <td class="text-right"><strong>{{ total.title }}:</strong></td>
              <td class="text-right">{{ total.text }}</td>
            </tr>
            {% endfor %}
          </table>
        </div>
      </div>
      <div class="buttons clearfix">
        <div class="pull-left"><a href="{{ continue }}" class="btn btn-default">{{ button_shopping }}</a></div>
        <div class="pull-right"><a href="{{ checkout }}" class="btn btn-primary">{{ button_checkout }}</a></div>
      </div>
      {{ content_bottom }}</div>
    {{ column_right }}</div>
</div>
<!--添加更新和删除JS-->
<script type="text/javascript">
$('.update-cart').on('click',function(){
  $.ajax({
    url: 'index.php?route=checkout/cart/edit',
    type: 'post',
    data: $('input[name^=\'quantity\']'),
    dataType: 'json',
    beforeSend: function() {
      $(".update-cart").attr('disabled',true);
    },
    complete: function() {
      $(".update-cart").attr('disabled',false);
    },
    success: function(json) {
      if(json['success']){
        $('.alert-success').fadeOut();
        $('.breadcrumb').after('<div class="alert alert-success"><i class="fa fa-check-circle"></i>'+json['success']+'<button type="button" class="close" data-dismiss="alert"> × </button></div>');
        $('#cart > button').html('<span id="cart-total"><i class="fa fa-shopping-cart"></i> ' + json['total'] + '</span>');

        $('#cart > ul').load('index.php?route=common/cart/info ul li');
      }

      html = '';

      if (json['totals'] != '') {
        for (i = 0; i < json['totals'].length; i++) {
          html += '<tr> <td class="text-right"><strong>' + json['totals'][i]['title'] +'</strong></td><td class="text-right">' + json['totals'][i]['text'] +'</td> </tr>';
        }
        $('.total-table').html(html);
      }

      if(json['update']){
        location = 'index.php?route=checkout/cart';
      }

    },
    error: function(xhr, ajaxOptions, thrownError) {
      alert(thrownError + "\r\n" + xhr.statusText + "\r\n" + xhr.responseText);
    }
  })
});
 //删除商品js
$(".remove-cart").on('click',function(){
  var cart_id = $(this).attr('data-cart-id');
  var elv = $(this).parents('.product-thumb');
  $.ajax({
    url: 'index.php?route=checkout/cart/remove',
    type: 'post',
    data: 'key=' + cart_id,
    dataType: 'json',
    beforeSend: function() {
      $(".remove-cart").attr('disabled',true);
    },
    complete: function() {
      $(".remove-cart").attr('disabled',false);
    },
    success: function(json) {

      if(json['success']){
        elv.fadeOut();
        $('.alert-success').remove();
        $('.breadcrumb').after('<div class="alert alert-success"><i class="fa fa-check-circle"></i> '+json['success']+'<button type="button" class="close" data-dismiss="alert"> × </button></div>');
        $('#cart > button').html('<span id="cart-total"><i class="fa fa-shopping-cart"></i> ' + json['total'] + '</span>');
        $('#cart > ul').load('index.php?route=common/cart/info ul li');
      }

      html = '';

      if (json['totals'] != '') {
        for (i = 0; i < json['totals'].length; i++) {
          html += '<tr> <td class="text-right"><strong>' + json['totals'][i]['title'] +'</strong></td><td class="text-right">' + json['totals'][i]['text'] +'</td> </tr>';
        }
        $('.total-table').html(html);
      }

      if(json['update']){
        location = 'index.php?route=checkout/cart';
      }

    },
    error: function(xhr, ajaxOptions, thrownError) {
      alert(thrownError + "\r\n" + xhr.statusText + "\r\n" + xhr.responseText);
    }
  });
});
</script>
<!--添加更新和删除JSend-->
{{ footer }}

下面是控制器文件（路径catalog\controller\checkout\cart.php），我只摘要了需要修改的两个代码方法片段，一个是public function edit (）方法一个是public function remove (）方法

public function edit() {
   $this->load->language('checkout/cart');

   $json = array();

   // Update
   if (!empty($this->request->post['quantity'])) {
      foreach ($this->request->post['quantity'] as $key => $value) {
         $this->cart->update($key, $value);
      }

      $this->session->data['success'] = $this->language->get('text_remove');

      $json['success'] = $this->language->get('text_remove');//添加更新说明

      unset($this->session->data['shipping_method']);
      unset($this->session->data['shipping_methods']);
      unset($this->session->data['payment_method']);
      unset($this->session->data['payment_methods']);
      unset($this->session->data['reward']);

      //添加金额计算
      // Totals
      $this->load->model('setting/extension');

      $totals = array();
      $taxes = $this->cart->getTaxes();
      $total = 0;

      // Because __call can not keep var references so we put them into an array.
      $total_data = array(
         'totals' => &$totals,
         'taxes'  => &$taxes,
         'total'  => &$total
      );

      // Display prices
      if ($this->customer->isLogged() || !$this->config->get('config_customer_price')) {
         $sort_order = array();

         $results = $this->model_setting_extension->getExtensions('total');

         foreach ($results as $key => $value) {
            $sort_order[$key] = $this->config->get('total_' . $value['code'] . '_sort_order');
         }

         array_multisort($sort_order, SORT_ASC, $results);

         foreach ($results as $result) {
            if ($this->config->get('total_' . $result['code'] . '_status')) {
               $this->load->model('extension/total/' . $result['code']);

               // We have to put the totals in an array so that they pass by reference.
               $this->{'model_extension_total_' . $result['code']}->getTotal($total_data);
            }
         }

         $sort_order = array();

         foreach ($totals as $key => $value) {
            $sort_order[$key] = $value['sort_order'];
         }

         array_multisort($sort_order, SORT_ASC, $totals);
      }

      $json['total'] = sprintf($this->language->get('text_items'), $this->cart->countProducts() + (isset($this->session->data['vouchers']) ? count($this->session->data['vouchers']) : 0), $this->currency->format($total, $this->session->data['currency']));

      $json['totals'] = array();

      foreach ($totals as $total) {
         $json['totals'][] = array(
            'title' => $total['title'],
            'text'  => $this->currency->format($total['value'], $this->session->data['currency'])
         );
      }

      if(!$this->cart->countProducts()){
         $json['update'] = true;
      }

   }

   $this->response->addHeader('Content-Type: application/json');
   $this->response->setOutput(json_encode($json));
}

    public function remove() {
      $this->load->language('checkout/cart');

      $json = array();

      // Remove
      if (isset($this->request->post['key'])) {
         $this->cart->remove($this->request->post['key']);

         unset($this->session->data['vouchers'][$this->request->post['key']]);

         $json['success'] = $this->language->get('text_remove');

         unset($this->session->data['shipping_method']);
         unset($this->session->data['shipping_methods']);
         unset($this->session->data['payment_method']);
         unset($this->session->data['payment_methods']);
         unset($this->session->data['reward']);

         // Totals
         $this->load->model('setting/extension');

         $totals = array();
         $taxes = $this->cart->getTaxes();
         $total = 0;

         // Because __call can not keep var references so we put them into an array.          
         $total_data = array(
            'totals' => &$totals,
            'taxes'  => &$taxes,
            'total'  => &$total
         );

         // Display prices
         if ($this->customer->isLogged() || !$this->config->get('config_customer_price')) {
            $sort_order = array();

            $results = $this->model_setting_extension->getExtensions('total');

            foreach ($results as $key => $value) {
               $sort_order[$key] = $this->config->get('total_' . $value['code'] . '_sort_order');
            }

            array_multisort($sort_order, SORT_ASC, $results);

            foreach ($results as $result) {
               if ($this->config->get('total_' . $result['code'] . '_status')) {
                  $this->load->model('extension/total/' . $result['code']);

                  // We have to put the totals in an array so that they pass by reference.
                  $this->{'model_extension_total_' . $result['code']}->getTotal($total_data);
               }
            }

            $sort_order = array();

            foreach ($totals as $key => $value) {
               $sort_order[$key] = $value['sort_order'];
            }

            array_multisort($sort_order, SORT_ASC, $totals);
         }

         $json['total'] = sprintf($this->language->get('text_items'), $this->cart->countProducts() + (isset($this->session->data['vouchers']) ? count($this->session->data['vouchers']) : 0), $this->currency->format($total, $this->session->data['currency']));
//更新订单小计
         $json['totals'] = array();

         foreach ($totals as $total) {
            $json['totals'][] = array(
               'title' => $total['title'],
               'text'  => $this->currency->format($total['value'], $this->session->data['currency'])
            );
         }

         if(!$this->cart->countProducts()){
            $json['update'] = true;
         }
      }

      $this->response->addHeader('Content-Type: application/json');
      $this->response->setOutput(json_encode($json));
   }