Laravel:如何从此数据透视表 table 获取数据?

Laravel: How do I get data from this pivot table?

已解决:下面发布了答案

如何从这个数据透视表和规范中获取值 table?

我想在这样的模板中显示它:

-型号(规格名称table)

--品牌(属性形式枢轴table):example1(来自枢轴table的值)

--模型(属性形式枢轴table):example123(来自枢轴table的值) ...


在 ProductController 中,我尝试返回类似 $product = Product::with('specifications')->first(); 的内容,但随后我只能从规格 table 中获取数据,如果我尝试 $product = Product::with('product_specification')->first();,我会收到错误 Call to undefined relationship [product_specification] on model [App\Product].


枢轴table:

public function up()
{
    Schema::create('product_specification', function (Blueprint $table) {
        $table->engine = 'InnoDB';

        $table->increments('id');
        $table->integer('product_id')->unsigned()->index();
        $table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
        $table->integer('specification_id')->unsigned()->index();
        $table->foreign('specification_id')->references('id')->on('specifications')->onDelete('cascade');
        $table->string('attribute');
        $table->string('value');
    });
}

规格table:

public function up()
{
    Schema::create('specifications', function (Blueprint $table) {
        $table->engine = 'InnoDB';

        $table->increments('id');
        $table->string('name')->unique();
        $table->timestamps();
    });
}

产品型号:

public function specifications() 
{
    return $this->belongsToMany(Specification::class, 'product_specification');
}

我必须将 withPivot() 添加到我的产品模型中

public function specifications() {
    return $this->belongsToMany(Specification::class, 'product_specification')->withPivot('attribute', 'value');
}

然后在模板中:

foreach($product->specifications as $specification) {
    echo 'name: ' . $specification->name . ' attribute: ' . $specification->pivot->attribute . ' value ' . $specification->pivot->value . '</br>';
}