使用多对多关联，完成用户关注与取关操作

Author: dongjun2000

app/Http/Controllers/UserController.php

@@ -70,6 +70,18 @@ public function store(Request $request)
        return redirect()->route('home')->with('success', '注册成功！并已为你自动登录~~~');
     }
 
+    /**
+     * 关注与取关
+     * @param User $user
+     * @return \Illuminate\Http\RedirectResponse
+     */
+    public function follow(User $user)
+    {
+        $user->followToggle(\Auth::user()->id);
+
+        return back();
+    }
+
     /**
      * 用户个人主页
      *
@@ -79,7 +91,14 @@ public function store(Request $request)
     public function show(User $user)
     {
         $blogs = Blog::where('user_id', $user->id)->orderBy('id', 'DESC')->paginate(10);
-        return view('user.show', compact('user', 'blogs'));
+
+        // 关注状态
+        $followStatus = '关注我';
+        if (\Auth::check()) {
+            $followStatus = $user->isFollow(\Auth::user()->id) ? '取消关注' : '关注我';
+        }
+
+        return view('user.show', compact('user', 'blogs', 'followStatus'));
     }
 
     /**

app/User.php

@@ -35,4 +35,46 @@ public function blogs()
     {
         return $this->hasMany(Blog::class);
     }
+
+    /**
+     * 我的关注
+     */
+    public function follows()
+    {
+        return $this->belongsToMany(User::class, 'follows', 'fans', 'user_id')->withTimestamps();
+    }
+
+    /**
+     * 我的粉丝
+     *
+     * 点击关注，往user_id里面插入被关注者id，在fans插入我的id
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
+     */
+    public function fans()
+    {
+        return $this->belongsToMany(User::class, 'follows', 'user_id', 'fans')->withTimestamps();
+    }
+
+    /**
+     * 查询指定用户是否是我的粉丝
+     *
+     * @param $uid
+     * @return mixed
+     */
+    public function isFollow($uid)
+    {
+        return $this->fans()->wherePivot('fans', $uid)->first();
+    }
+
+    /**
+     * 关注与取关
+     *
+     * @return array
+     */
+    public function followToggle($ids)
+    {
+        $ids = is_array($ids) ?: [$ids];
+        return $this->fans()->toggle($ids);
+    }
 }

database/migrations/2019_09_06_011652_create_follows_table.php

@@ -0,0 +1,33 @@
+<?php
+
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class CreateFollowsTable extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        Schema::create('follows', function (Blueprint $table) {
+            $table->increments('id');
+            $table->integer('user_id');
+            $table->integer('fans');
+            $table->timestamps();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        Schema::dropIfExists('follows');
+    }
+}

resources/views/user/show.blade.php

@@ -4,6 +4,11 @@
     <div class="card">
         <div class="card-header">
             <h1 class="text-center">{{$user['name']}}</h1>
+            <div class="text-center">
+                <a href="" class="btn btn-danger">我的关注:{{$user->follows()->count()}}</a>
+                <a href="" class="btn btn-dark">我的粉丝:{{$user->fans()->count()}}</a>
+                <a class="btn btn-success" href="{{ route('userFollow', $user) }}" role="button">{{ $followStatus }}</a>
+            </div>
         </div>
         <div class="card-body">
             <table class="table">

routes/web.php

@@ -29,4 +29,11 @@
 Route::post('findPassword', 'PasswordController@findPassword')->name('findPassword');
 
 Route::get('resetPassword/{token}', 'PasswordController@resetPasswordForm')->name('resetPassword');
-Route::post('resetPassword', 'PasswordController@resetPassword')->name('resetPasswordStore');
+Route::post('resetPassword', 'PasswordController@resetPassword')->name('resetPasswordStore');
+
+// 关注与取关
+Route::get('follow/{user}', 'UserController@follow')->name('userFollow');
+
+// 我的粉丝
+
+// 我关注的