Laravel 5.5：在集合实例上获取多对多的响应

Question

Blog和Category之间有很多关系。

blog.php的

public function category() {
    return $this->belongsToMany('App\Category');
}

Category.php

public function blog() {
    return $this->belongsToMany('App\Blog');
}

create_blogs_table.php

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateBlogsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('blogs', function (Blueprint $table) {
            $table->increments('id');
            $table->string('title')->length(250);
            $table->text('content');
            $table->integer('updated_by')->unsigned()->nullable();
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('blogs');
    }
}

create_categories_table.php

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateCategoriesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('categories', function (Blueprint $table) {
            $table->increments('id');
            $table->string('name')->length(250);
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('categories');
    }
}

blog_category_table.php

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class BlogCategoryTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create ( 'blog_category', function (Blueprint $table) {
            $table->integer ( 'category_id' )->unsigned ();
            $table->integer ( 'blog_id' )->unsigned ();

            $table->foreign ( 'category_id' )->references ( 'id' )->on ( 'categories' );
            $table->foreign ( 'blog_id' )->references ( 'id' )->on ( 'blogs' );

            $table->primary ( [
                    'category_id',
                    'blog_id'
            ]);
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists ( 'blog_category' );
    }
}

要获得与我可以编码的任何类别相关的博客

$category = App\Category::find(1);
$category->blog->get();

但是，如果我想获得与类别ID为1＆amp;的类别相关的博客2在一个查询中。应该解决这个问题的方法是什么？

我尝试了同样的方法，它给我的错误就像 '带有消息的异常'此属性[博客]在此集合实例上不存在。'