<div class="row">
        <div class="well">
            <form id="uploadform">
                <div class="control-group form-group"><input class="form-control" id='productname' type='text' placeholder='Productnaam' /></div>
                <div class="control-group form-group"><textarea class="form-control" id='description' placeholder='Beschrijving'></textarea></div>
                <div class="control-group form-group">
                    <?php 
$db = select_sql("SELECT guid FROM category");
$limit = ceil(count($db) / 3);
$counter = 0;
foreach ($db as $data) {
    if ($counter % $limit == 0) {
        echo '<div class="col-md-4">';
    }
    $c = new Category();
    $c->loadByGUID($data['guid']);
    echo '<input type="checkbox" value="' . $c->name . '">' . $c->name . '<br />';
    if (($counter + 1) % $limit == 0) {
        echo '</div>';
    }
    $counter++;
}
if ($counter !== 0) {
    echo '</div>';
}
?>
                </div>
                <div class="control-group form-group">
                    <label>Verloten in</label>
                    <div class="dropdown">
                        <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu1" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
                <!-- Brand and toggle get grouped for better mobile display -->
                <div class="navbar-header">
                    <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-2">
                        <span class="sr-only">Toggle navigation</span>
                        <span class="icon-bar"></span>
                        <span class="icon-bar"></span>
                        <span class="icon-bar"></span>
                    </button>
                </div>
				<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-2"> 
					<div class="categories">
						<?php 
$sql = select_sql("SELECT guid FROM category");
foreach ($sql as $s) {
    $categoryl = new Category();
    $categoryl->loadByGUID($s['guid']);
    echo '<a href="' . $categoryl->getURL() . '">' . $categoryl->name . '</a>';
}
?>
					</div>
				</div>
                <!-- Collect the nav links, forms, and other content for toggling -->
                <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-2">
                    <ul class="nav navbar-nav navbar-rleft">
                        
                    </ul>
                </div>
                <!-- /.navbar-collapse -->
            </div>
            <!-- /.container -->
        </nav>
 /**
  * @return Category[]
  */
 public function getCategories()
 {
     if ($this->categories == array()) {
         $r = select_sql("SELECT category_guid FROM product_has_category WHERE product_guid = ?", 's', $this->guid);
         foreach ($r as $c) {
             $category = new Category();
             $category->loadByGUID($c['category_guid']);
             array_push($this->categories, $category);
         }
     }
     return $this->categories;
 }