//与课程标签联合表的一对多关系
public function hasManyLessonTags(){return $this->hasMany(\App\Model\Admin\TagAndLesson::class,'tl_l_id','l_id');
}

//2、插入标签课程数据--关系表
$tags=$request['tags'];
foreach ($tags as $tag){$tag_lesson=[];$tag_lesson['tl_t_id']=$tag;//$tag_lesson['tl_l_id']=$lesson['l_id'];//TagAndLesson::create($tag_lesson);//dd($tag_lesson);$lesson->hasManyLessonTags()->create($tag_lesson);}

CREATE TABLE `lessons`  (`l_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,`l_title` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL,`l_introduce` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL,`l_preview` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL,`l_is_commend` tinyint(4) NOT NULL,`l_is_hot` tinyint(4) NOT NULL,`l_click` int(11) NOT NULL DEFAULT 0 COMMENT '点击数/浏览数',`l_like` int(11) NOT NULL DEFAULT 0 COMMENT '点赞数',`l_comment_num` int(11) NOT NULL DEFAULT 0 COMMENT '评论数',`created_at` timestamp(0) NULL DEFAULT NULL,`updated_at` timestamp(0) NULL DEFAULT NULL,PRIMARY KEY (`l_id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 27 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;

CREATE TABLE `tags`  (`t_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,`t_name` varchar(100) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL,`created_at` timestamp(0) NULL DEFAULT NULL,`updated_at` timestamp(0) NULL DEFAULT NULL,PRIMARY KEY (`t_id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 4 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;

CREATE TABLE `tag_and_lessons`  (`tl_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,`tl_t_id` int(11) NOT NULL COMMENT '标签id',`tl_l_id` int(11) NOT NULL COMMENT '课程id',`created_at` timestamp(0) NULL DEFAULT NULL,`updated_at` timestamp(0) NULL DEFAULT NULL,PRIMARY KEY (`tl_id`) USING BTREE,INDEX `tag_and_lessons_tl_t_id_index`(`tl_t_id`) USING BTREE,INDEX `tag_and_lessons_tl_l_id_index`(`tl_l_id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 15 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;

 1 <?php
 2
 3 namespace App\Model;
 4
 5 use Illuminate\Database\Eloquent\Model;
 6
 7 class Lesson extends Model
 8 {
 9     protected $primaryKey='l_id';
10     /**
11      * 与视频表模型的一对多关联
12      * @return \Illuminate\Database\Eloquent\Relations\HasMany
13      */
14     public function videos(){
15         return $this->hasMany(Video::class,'v_l_id','l_id');
16     }
17
18     //与标签的多对多关系
19     public function hasManyTags(){
20         return $this->belongsToMany('App\Model\Tag','tag_and_lessons','tl_l_id','tl_t_id');
21     }
22
23     //与课程标签联合表的一对多关系
24     public function hasManyLessonTags(){
25         return $this->hasMany(\App\Model\Admin\TagAndLesson::class,'tl_l_id','l_id');
26     }
27 }

<?phpnamespace App\Model;use Illuminate\Database\Eloquent\Model;class Tag extends Model
{//$guarded表示不允许批量填充的字段protected $primaryKey='t_id';protected $guarded=[];}

<?phpnamespace App\Model\Admin;use Illuminate\Database\Eloquent\Model;class TagAndLesson extends Model
{//
    protected $primaryKey='tl_id';protected $guarded=[];
}

 1     public function store(Request $request,Lesson $lesson)
 2     {
 3         DB::transaction(function () use ($request,$lesson) {
 4             //dd($request->toArray());
 5             $lesson['l_title']=$request['l_title'];
 6             $lesson['l_introduce']=$request['l_introduce'];
 7             $lesson['l_preview']=$request['l_preview'];
 8             $lesson['l_is_commend']=$request['l_is_commend'];
 9             $lesson['l_is_hot']=$request['l_is_hot'];
10             $lesson['l_click']=$request['l_click'];
11             $lesson->save();
12             //dd($lesson['l_id']);
13             //dd($lesson->toArray());
14
15             //2、插入标签课程数据--关系表
16             $tags=$request['tags'];
17             foreach ($tags as $tag){
18                 $tag_lesson=[];
19                 $tag_lesson['tl_t_id']=$tag;
20                 //$tag_lesson['tl_l_id']=$lesson['l_id'];
21                 //TagAndLesson::create($tag_lesson);
22                 //dd($tag_lesson);
23                 $lesson->hasManyLessonTags()->create($tag_lesson);
24
25             }
26
27
28             //videos数据过来的时候是json数据,true表示转成数组而非对象
29             $videos=json_decode($request['videos'],true);
30             //dd($videos);
31             foreach ($videos as $video){
32                 unset($video['v_id']);
33                 $lesson->videos()->create($video);
34 //            $lesson->videos()->create([
35 //                'title'=>$video['title'],
36 //                'path'=>$video['path'],
37 //            ]);
38             }
39         });
40
41
42         return redirect('/admin/lesson');
43
44
45     }