PHP上传图片但未显示

Question

这是我的功能add_product

function add_product() {

if(isset($_POST['publish'])) {

$product_title        = escape_string($_POST['product_title']);
$product_category_id  = escape_string($_POST['product_category_id']);
$product_price        = escape_string($_POST['product_price']);
$product_quantity     = escape_string($_POST['product_quantity']);
$product_description  = escape_string($_POST['product_description']);
$short_desc           = escape_string($_POST['short_desc']);
$product_image        = $_FILES['file']['name'];
$image_temp_location  = $_FILES['file']['tmp_name'];

move_uploaded_file($image_temp_location, UPLOAD_DIRECTORY . DS . $product_image );


$query = query("INSERT INTO products(product_title, product_category_id, 
product_price, product_quantity, product_description, short_desc, product_image) VALUES('{$product_title}', '{$product_category_id}', 
'{$product_price}', '{$product_quantity}', '{$product_description}', '{$short_desc}', '{$product_image}')");
$last_id = last_id();
confirm($query);
set_message("New Product with id {$last_id} was Added");
redirect("index.php?products");

      }
}

这是函数get_products_in_admin

function get_products_in_admin(){

$query = query(" SELECT * FROM products");
confirm($query);

 while($row = fetch_array($query)) {

 $category = show_product_category_title($row['product_category_id']);

$product = <<<DELIMETER

  <tr>
     <td>{$row['product_id']}</td>
     <td>{$row['product_title']}<br>
     <a href="index.php?edit_product&id={$row['product_id']}" ><img width='100' src="../../resources/uploads{$row['product_image']}" alt=""></a>
    </td>
     <td>{$category}</td>
     <td>{$row['product_price']}</td>
     <td>{$row['product_quantity']}</td>
     <td><a class="btn btn-danger" 
href="../../resources/templates/back/delete_product.php?id= 
  {$row['product_id']}"><span class="glyphicon glyphicon-remove"></span></a> 
</td>
 </tr>

DELIMETER;

 echo $product;


    }

这是我的html（add_product.php）

<?php add_product(); ?>
<div class="col-md-12">

<div class="row">
<h1 class="page-header">
  Add Product

</h1>
</div>



<form action="" method="post" enctype="multipart/form-data">


<div class="col-md-8">

<div class="form-group">
<label for="product-title">Product Title </label>
    <input type="text" name="product_title" class="form-control">

</div>


<div class="form-group">
       <label for="product-title">Product Description</label>
  <textarea name="product_description" id="" cols="30" rows="10" class="form- 
 control"></textarea>
</div>



<div class="form-group row">

  <div class="col-xs-3">
    <label for="product-price">Product Price</label>
    <input type="number" name="product_price" class="form-control" size="60">
  </div>
  </div>


 <div class="form-group">
       <label for="product-title">Product Short Description</label>
  <textarea name="short_desc" id="" cols="30" rows="3" class="form-control"> 
 </textarea>
 </div>





 </div><!--Main Content-->


<!-- SIDEBAR-->


<aside id="admin_sidebar" class="col-md-4">


 <div class="form-group">
   <input type="submit" name="draft" class="btn btn-warning btn-lg" 
value="Draft">
    <input type="submit" name="publish" class="btn btn-primary btn-lg" 
value="Publish">
</div>


 <!-- Product Categories-->

 <div class="form-group">
     <label for="product-title">Product Category</label>
    <select name="product_category_id" id="" class="form-control">
        <option value="">Select Category</option>
       <?php show_categories_add_product_page(); ?>

    </select>


</div>





 <!-- Product Brands-->


 <div class="form-group">

    <label for="product-quantity">Product Quantity</label>
    <input type="number" name="product_quantity" class="form-control" 
 size="60">

</div>


<!-- Product Tags -->


 <!--  <div class="form-group">
      <label for="product-title">Product Keywords</label>
      <hr>
    <input type="text" name="product_tags" class="form-control">
-->
 <!-- Product Image -->
 <div class="form-group">
     <label for="product-title">Product Image</label>
     <input type="file" name="file">

 </div>



</aside><!--SIDEBAR-->



</form>

这是三个文件。函数内部的functions.php（有我的函数add_product和get_products_in_admin。最后一个是add_product.php 我有一个问题，因为上传产品后图像未显示。