mtb_dcatadmin_plus/app/Models/DistProductCategory.php

<?php

namespace App\Models;

use Dcat\Admin\Traits\HasDateTimeFormatter;

use Dcat\Admin\Traits\ModelTree;
use Illuminate\Database\Eloquent\Model;
use Spatie\EloquentSortable\Sortable;

class DistProductCategory extends Model implements Sortable
{
    use HasDateTimeFormatter,
        ModelTree {
        ModelTree::boot as treeBoot;
    }
	use HasDateTimeFormatter;
    protected $table = 'dist_product_category';

    //名称
    protected $titleColumn = 'name';
    //排序
    protected $orderColumn = 'order';
    //父级
    protected $parentColumn = 'parent_id';


    protected $casts = [
        'created_at' => 'datetime:Y-m-d H:i:s',
        'updated_at' => 'datetime:Y-m-d H:i:s',
    ];

    /*
     * 关联产品参数
     */
    public function distProductParameter()
    {
        return $this->hasOne(DistProductParameter::class,'id','parameter_id');
    }


    public static function selectOptions(\Closure $closure = null)
    {
        $options = (new static())->withQuery($closure)->buildSelectOptions();
        return collect($options)->all();
    }
    public function getAllCategories($parentId = null)
    {
        // Retrieve categories with the specified parentId, or all if no parentId is specified
        $query = self::query();

        if ($parentId !== null) {
            $query->where('parent_id', $parentId);
        }

        $categories = $query->orderBy($this->orderColumn)->get();

        // If you want a hierarchical structure, you can recursively build it
        $categories->each(function ($category) {
            $category->children = $category->getAllCategories($category->id);
        });

        return $categories;
    }

}