Laravel模型中的空關系

這些是我的遷移

型別遷移

 Schema::create('digital_types', function (Blueprint $table) {
            $table->id();
            $table->string('name');
            $table->timestamps();
        });

內容遷移

Schema::create('digital_products', function (Blueprint $table) {
            $table->id();
            $table->unsignedBigInteger('product_type_id')->nullable();
            $table->string('name');
            $table->unsignedTinyInteger('status')->default(1);
            $table->softDeletes();
            $table->timestamps();
            $table->foreign('product_type_id')->references('id')->on('digital_types')->nullOnDelete()->cascadeOnUpdate();
        });

模型定義：

型別 型號

class DigitalType extends Model
{
    use HasFactory;
    public function digitalContents() {
        return $this->hasMany(DigitalProduct::class);
    }
}

內容模型

class DigitalProduct extends Model
{
    use HasFactory;
    public function digitalContentType() {
        return $this->belongsTo(DigitalType::class);
    }

    public function categories(){
        return $this->belongsToMany(Category::class, 'digital_product_category');
    }
}

但是當我想通過方法獲取我的Contentwith TypeRelation 時with，它回傳NULL.

我的控制器

class DigitalProductController extends Controller
{
    public function productsList(){
        $products= DigitalProduct::with('digitalContentType')->get();
        echo $products;
        // return view('pages.digitalproducts', compact('products'));
    }
}

并且echo瀏覽器中的資料控制器為空（這兩行的結尾）

[{"id":1,"product_type_id":1,"name":"deserunt","description":"Id nam amet voluptatibus quia.","image_url":null,"content_url":null,"price":"3.00","discount":"7.00","status":1,"deleted_at":null,"created_at":"2021-12-29T13:47:41.000000Z","updated_at":"2021-12-29T13:47:41.000000Z","digital_content_type":null},

{"id":2,"product_type_id":3,"name":"aut","description":"Saepe ratione soluta aspernatur aspernatur debitis dolor.","image_url":null,"content_url":null,"price":"8.00","discount":"7.00","status":1,"deleted_at":null,"created_at":"2021-12-29T13:47:41.000000Z","updated_at":"2021-12-29T13:47:41.000000Z","digital_content_type":null},

另一件事是我的資料庫填充了虛假資料，對于Content和Type

 ---- ------------ ------------ ------------ 
| id | name       | created_at | updated_at |
 ---- ------------ ------------ ------------ 
|  1 | ebook      | NULL       | NULL       |
|  2 | audio book | NULL       | NULL       |
|  3 | magazin    | NULL       | NULL       |
|  4 | news paper | NULL       | NULL       |
 ---- ------------ ------------ ------------ 

 ---- ----------------- ------------ ---------------------------------------------------------------- ----------- ------------- ------- ---------- -------- ------------ --------------------- --------------------- 
| id | product_type_id | name       | description                                                    | image_url | content_url | price | discount | status | deleted_at | created_at          | updated_at          |
 ---- ----------------- ------------ ---------------------------------------------------------------- ----------- ------------- ------- ---------- -------- ------------ --------------------- --------------------- 
|  1 |               1 | deserunt   | Id nam amet voluptatibus quia.                                 | NULL      | NULL        |  3.00 |     7.00 |      1 | NULL       | 2021-12-29 13:47:41 | 2021-12-29 13:47:41 |
|  2 |               3 | aut        | Saepe ratione soluta aspernatur aspernatur debitis dolor.      | NULL      | NULL        |  8.00 |     7.00 |      1 | NULL       | 2021-12-29 13:47:41 | 2021-12-29 13:47:41 |

uj5u.com熱心網友回復：

我認為問題是 digital_products 中的外國 ID 列沒有 Laravel 標準的名稱。

如果列名不是 Laravel 標準的，你必須在 realtionship 方法中指定它：

public function digitalContentType() {
    return $this->belongsTo(DigitalType::class, 'product_type_id');
}

標籤：拉拉维尔 雄辩 laravel-关系 laravel 模型

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