exception: "ErrorException"
file: "/Users/ray/shoes-manage/vendor/dcat/laravel-admin/src/Form/Field/Table.php"
line: 73
message: "Undefined index: _remove_"

            $form->table('item', function (Form\NestedForm $table) {
                $table->select('item_id', '所属分类')->options(function ($id) {
                    $item = Item::find($id);
                    if ($item) {
                        return [$item->id => $item->name];
                    }
                })->ajax('api/item')->required();
                $table->decimal('price', '价格')->required();
            });

    public function item(): BelongsToMany
    {
        $pivotTable = 'order_item'; // 中间表

        $relatedModel = Item::class; // 关联模型类名

        return $this->belongsToMany($relatedModel, $pivotTable, 'order_id', 'item_id');
    }

    public function order(): BelongsToMany
    {
        $pivotTable = 'order_item'; // 中间表

        $relatedModel = Order::class; // 关联模型类名

        return $this->belongsToMany($relatedModel, $pivotTable, 'item_id', 'order_id');
    }