如何从Laravel中的嵌套关​​系中获取所有记录

如何解决如何从Laravel中的嵌套关​​系中获取所有记录

我想基于project_id从表Tasks中获取记录。但是我找不到我想要的结果。 我的项目模型代码：

class Project extends Model
{
    function progress(){
        return $this->hasMany(Progress::class);
    }
}

进度模型代码：

class Progress extends Model
{
    function project(){
        return $this->belongsTo(Project::class);
    }

    function task(){
        return $this->hasMany(Task::class);
    }
}

任务模型代码：

class Task extends Model
{

    protected $fillable = [
        'progress',];

    function progress(){
        return $this->belongsTo(Progress::class,'id');
    }
}

这是我的控制器功能：

public function task_project_view_detail($id){
        $project = Project::with(['user','image','document','progress.task'])->where('id',$id)->first();
        $progress = $project->progress;
        return view('admin.tasks.project-view',['progress' => $progress])->with('project',$project);
    }

这是我的查看文件：

@foreach ($progress as $prog)
  @foreach ($prog->task as $tasks)
    <li class="task">
      <div class="task-container">
        <span class="task-action-btn task-check">
          <a href="" style="background:#3d981f;" class="action-circle large complete-btn" title="Mark Complete">
            <i class="material-icons">check</i>
          </a>
        </span>
        <span class="task-label" contenteditable="true">{{ $tasks->name }}</span>
        <span class="task-action-btn task-btn-right">
          <a href="" class="action-circle large" title="Delete Task">
            <i class="material-icons">delete</i>
          </a>
        </span>
      </div>
    </li>
  @endforeach
@endforeach

这是我的结果： there should be only first 3 rows,but all tasks in this project are showing.

There should be only 1 row,the 4th one.

这是项目模型的架构：

Schema::create('projects',function (Blueprint $table) {
            $table->id();
            $table->unsignedInteger('user_id')->nullable();
            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade')->onUpdate('cascade');
            $table->string('title');
            $table->timestamps();
});

这是进度模型的模式：

Schema::create('progress',function (Blueprint $table) {
            $table->id();
            $table->unsignedInteger('project_id')->nullable();
            $table->foreign('project_id')->references('id')->on('projects')->onDelete('cascade')->onUpdate('cascade');
            $table->string('name');
            $table->timestamps();
});

这是任务模型的架构：

Schema::create('tasks',function (Blueprint $table) {
            $table->id();
            $table->unsignedInteger('progress_id')->nullable();
            $table->foreign('progress_id')->references('id')->on('progress')->onDelete('cascade')->onUpdate('cascade');
            $table->string('name')->nullable();
            $table->string('status')->nullable();
            $table->timestamps();
});

我该怎么办？

解决方法

has-many-through关系为通过中间关系访问远处的关系提供了方便的快捷方式。在您的情况下，您可以这样使用： 在项目模型中定义tasks()：

public function tasks()
{
     return $this->hasManyThrough('App\Task','App\Progress');
}

传递给hasManyThrough方法的第一个参数是我们希望访问的最终模型的名称，而第二个参数是中间模型的名称。

要获得项目任务，您可以在控制器中执行以下操作：

public function task_project_view_detail($id){
   $project = Project::with(['user','image','document','tasks'])->where('id',$id)->first();
   $tasks= $project->tasks;
   return view('admin.tasks.project-view',['tasks' => $tasks])->with('project',$project);
}

然后在视图中直接使用foreach，如下所示：

@foreach ($tasks as $task)