controller.php

$data["category_products"] = $this->product_model->get_products_by_category_id();

model.php

//get products by category ID
public function get_products_by_category_id()
{
    $lc_key = get_location_cache_key($this);
    $key = "special_offers_lang_" . $this->selected_lang->id;
    $result_cache = get_cached_data($this, $key, "pr");
    if (!empty($result_cache)) {
        if (!empty($result_cache[$lc_key])) {
            return $result_cache[$lc_key];
        }
    } else {
        $result_cache = array();
    }

    $this->build_query();
    $this->db->where('products.category_id', 1);
    $this->db->order_by('products.created_at', 'DESC')->limit(20);
    $result = $this->db->get('products')->result();

    $result_cache[$lc_key] = $result;
    set_cache_data($this, $key, $result_cache, "pr");
    return $result;
}

view.php

<?php foreach ($category_products as $product): ?>

<?php endforeach ?>

有了这个函数，我可以从类别ID 1中获取产品。
有没有办法使用这一个函数，并从视图传递到模型变量，我需要在foreach中获取哪个类别？
还是其他什么方式
例如：

<?php foreach ($category_products[1] as $product): ?>
    
    <?php endforeach ?>

或

<?php foreach ($category_products[2] as $product): ?>
    
    <?php endforeach ?>

@更新：
视图

<?php foreach ($this->product_model->get_products_by_category_id(1) as $product): ?>

控制器：

$data["category_products"] = $this->product_model->get_products_by_category_id($id);

型号：

//get products by category ID
    public function get_products_by_category_id($id)
    {
        $lc_key = get_location_cache_key($this);
        $key = "special_offers_lang_" . $this->selected_lang->id;
        $result_cache = get_cached_data($this, $key, "pr");
        if (!empty($result_cache)) {
            if (!empty($result_cache[$lc_key])) {
                return $result_cache[$lc_key];
            }
        } else {
            $result_cache = array();
        }

        $this->build_query();
        $this->db->where('products.category_id', $id);
        $this->db->order_by('products.created_at', 'DESC')->limit(20);
        $result = $this->db->get('products')->result();

        $result_cache[$lc_key] = $result;
        set_cache_data($this, $key, $result_cache, "pr");
        return $result;
    }

这工作正确，并给我正确的输出。但我也得到的问题：

Message: Undefined variable: id

Filename: controllers/Home_controller.php

当我从以下位置删除ID时：

$data["category_products"] = $this->product_model->get_products_by_category_id();

然后网站关闭：

Type: ArgumentCountError

Message: Too few arguments to function Product_model::get_products_by_category_id(), 0 passed in /home/design/domains/public_html/application/controllers/Home_controller.php on line 34 and exactly 1 expected