PHP嵌套的foreach循环

Question

所以基本上我想在第一个foreachloop中的每个项目上显示第二个foreach循环项目，但现在它只显示在第一个foreach循环的第一个项目而不是foreach循环中的每个项目。

我的变数：

        /* Queries */
$categories = $conn->query('SELECT pc.name, pc.ID, COUNT(p.id) AS amount FROM productcategory AS pc INNER JOIN products AS p ON p.categoryID = pc.ID WHERE p.available = 1 GROUP BY pc.ID');
$categories->execute();

$subcategories = $conn->query('SELECT pcs.name, pcs.categoryID, pcs.ID FROM productsubcategory AS pcs GROUP BY pcs.ID');
$subcategories->execute();

foreach ($categories as $category) {
                        if(isset($_GET['categorie'])) {
                            if($category["name"] === $_GET['categorie']) {
                                $class = 'class="selected"';
                            } else {
                                $class = '';
                            }
                        }
                        ?>
                        <li><a href="?categorie=<?php echo $category["name"]; ?>" <?php echo $class; ?>> <?php echo $category["name"] . ' ('. $category["amount"] .')'; ?></a></li>
                        <?php
                        foreach ($subcategories as $subcategory) {
                            if($subcategory['categoryID'] == $category['ID']) {
                                ?>
                                <li class="sub-cat"><a href="?categorie=<?php echo $subcategory["name"]; ?>" <?php echo $class; ?>> <?php echo $subcategory["name"]; ?></a></li>
                                <?php
                            }
                        }
                    }

输出

.sub-cat {
    margin-left: 10px;
    }

<ul>
                                        <li><a href="?categorie=Koffie"> Koffie (2)</a></li>
                                                        <li class="sub-cat"><a href="?categorie=extra sterk"> extra sterk</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Sterk"> Sterk</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Zoete"> Zoete</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Zoete"> Zoete</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Zoete"> Zoete</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Honing"> Honing</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Honing"> Honing</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Bon bons"> Bon bons</a></li>
                                                            <li class="sub-cat"><a href="?categorie=Puur"> Puur</a></li>
                                                    <li><a href="?categorie=Thee"> Thee (4)</a></li>
                                                <li><a href="?categorie=Chocolade"> Chocolade (2)</a></li>
                                                <li><a href="?categorie=Olie"> Olie (1)</a></li>
                                                <li><a href="?categorie=Wijn"> Wijn (2)</a></li>
                                                <li><a href="?categorie=Accessoires"> Accessoires (2)</a></li>
                                                <li><a href="?categorie=Cadeaus"> Cadeaus (1)</a></li>
                                    </ul>

预期产量： 所以基本上我想在正确的类别中显示好的子类别。我知道我需要使用if语句来比较子类别类别ID是否与类别ID相同，但第二个循环停止并且是第一个循环的第一个元素。

.sub-cat {
margin-left: 10px;
}

<ul>
    <li><a href="?categorie=Koffie"> Koffie (2)</a></li>
    <li class="sub-cat"><a href="?categorie=extrasterk"> extra sterk</a></li>
    <li class="sub-cat"><a href="categorie=Sterk"> Sterk</a></li>
    <li><a href="?categorie=Thee"> Thee (4)</a></li>
    <li class="sub-cat"><a href="?categorie=Zoete"> Zoete</a></li>
    <li class="sub-cat"><a href="?categorie=Zoete"> Zoete</a></li>
    <li class="sub-cat"><a href="?categorie=Zoete"> Zoete</a></li>
    <li class="sub-cat"><a href="?categorie=Honing"> Honing</a></li>
    <li class="sub-cat"><a href="?categorie=Honing"> Honing</a></li>
    <li><a href="?categorie=Chocolade"> Chocolade (2)</a></li>
    <li class="sub-cat"><a href="?categorie=Bon bons"> Bon bons</a></li>
    <li class="sub-cat"><a href="?categorie=Puur"> Puur</a></li>
    <li><a href="?categorie=Olie"> Olie (1)</a></li>
    <li><a href="?categorie=Wijn"> Wijn (2)</a></li>
    <li><a href="?categorie=Accessoires"> Accessoires (2)</a></li>
    <li><a href="?categorie=Cadeaus"> Cadeaus (1)</a></li>
</ul>