LARAVEL

Question

我想从类别对象访问主要类别，上面的 _id 列包含主要类别 ID。

错误：无法将 Illuminate\Database\Eloquent\Relations\BelongsTo 类型的对象用作数组

类别迁移：

Schema::create('categories', function (Blueprint $table) {
        $table->bigIncrements('id');
        $table->unsignedBigInteger('upper_id')->default(0);
        $table->string('name', 100);
        $table->string('slug', 100);
        $table->string('description', 500)->nullable();
        $table->timestamps();
        $table->softDeletes();
    });

类别模型：

class Category extends Model{
use SoftDeletes;
protected $fillable = ['upper_id', 'name', 'description', 'slug',];

public function companies()
{
    return $this->hasMany('App\Company', 'category_id', 'id');
}

public function up_category()
{
    $category = $this->belongsTo('App\Category', 'upper_id', 'id');
    return $category['name'];
}

类别控制器：

public function index()
{
    $categories = Category::where('deleted_at', null)->get();
    return view('admin.category.index', compact('categories'));
}

查看：

@foreach($categories as $category)
                        <tr>
                            <td>{{ $category->name }}</td>
                            <td>{{ $category->up_category->name }}</td>
                        </tr>
@endforeach

Answer 1

改变你的模型函数up_category

public function up_category(){
    return $this->belongsTo('App\Category', 'upper_id', 'id')->withDefault([
    'name' => '-'
   ]);
}

Blade 文件正确。

 <td>{{ $category->up_category->name }}</td> //No change

LARAVEL - 我想从包含主要类别 ID 的上 _id 列的类别对象访问主要类别

LARAVEL - I want to access the main category from the category object with the upper _id column that contains the main category ID

php

has-one

belongs-to

eloquent