文章对应分类多个

app/Models/Article.php

@@ -4,11 +4,12 @@ namespace App\Models;
 
 use App\Models\Traits\BelongsToCategory;
 use App\Models\Traits\HasOneCover;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 
 class Article extends Model
 {
 
-    use HasOneCover, BelongsToCategory;
+    use HasOneCover;
 
     /**
      * 应进行类型转换的属性
@@ -23,4 +24,35 @@ class Article extends Model
         return route('article.show', $this);
     }
 
+    /**
+     * Notes: 关联分类
+     * @Author: 玄尘
+     * @Date  : 2021/4/2 9:11
+     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
+     */
+    public function categories(): BelongsToMany
+    {
+        return $this->belongsToMany(Category::class)
+                    ->using(ArticleCategory::class);
+    }
+
+    /**
+     * Notes: description
+     * @Author: 玄尘
+     * @Date  : 2021/4/2 9:17
+     * @param $query
+     * @param $ids
+     * @return mixed
+     */
+    public function scopeByCategory($query, $ids)
+    {
+        if (!is_array($ids)) {
+            $ids = [$ids];
+        }
+
+        return $query->whereHas('categories', function ($q) use ($ids) {
+            $q->whereIN('id', $ids);
+        });
+    }
+
 }