Laravel 5.2:如何从一对一的eloquent(hasOne)关系中检索数据

时间:2016-04-15 02:00:22

标签: php laravel eloquent laravel-5.2 one-to-one

我有两个型号: 1.课程。 2.费用。

一门课程只收一费。虽然提供输入完全没问题但是当我尝试访问费用数据时,它在费用栏中没有显示任何内容。我该如何解决?

课程模型:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Course extends Model
{
    protected $table='courses';
    protected $fillable = ['name'];


    public function fee(){
        return $this->belongsTo('App\Fee');
    }

}

费用模式:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Fee extends Model
{
        protected $table='fees';
    protected $fillable = ['fee','course_id'];
    public function course()
    {
        return $this->hasOne('App\Course');
    }
}

控制器:

public function listofCourse(){
        $course=\App\Course::all();
        return view('listofCourse',compact('course'));
    }

查看页面:

<html>
    <head> 
        <title> Course Details </title>

    <link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">

    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script>
    <script src="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
    <script src="https://code.jquery.com/jquery-1.12.0.min.js"></script> 

    </head>
    <body>


<div class="container">
<h3> Student Details </h3>
      <table  class="table table-striped table-bordered"  id="example">
        <thead>
          <tr>
            <td>Serial No</td>
            <td>Course Name</td>
            <td>Course Fee</td>


        </tr>
        </thead>
        <tbody>
          <?php $i=1; ?>
        @foreach($course as $row)

          <tr>
            <td>{{$i}}</td>
            <td>{{$row->name }}</td>

            <td>    @if($row->course)
                  {{$row->course->fee}}
                   @endif</td>


             </tr>
          <?php $i++; ?>

        @endforeach
        </tbody>


      </table>

    </div>

    </body>
</html>

1 个答案:

答案 0 :(得分:6)

似乎你错误地写了关系......就这样做。

请注意,Course Has The Fee表示Course是必须的,因此关系应该从Course方向Fee开始。

您的课程模式

class Course extends Model
{
    protected $table='courses';
    protected $fillable = ['name'];


    public function fee(){
        return $this->hasOne('App\Fee','course_id', 'id');
    }

}

您的费用模式

class Fee extends Model
{
    protected $table='fees';
    protected $fillable = ['fee','course_id'];
    public function course()
    {
        return $this->belongsTO('App\Course', 'course_id', 'id');
    }
}

现在你可以通过这样做来获得这种关系。

public function listofCourse(){
        $course=\App\Course::with('fee')->get();
        // doing this for dumping purpose
        echo "<pre>"; 
        print_r($course->toArray()); // you will see the `fee` array
        echo "</pre>"; 
        die();
        return view('listofCourse',compact('course'));
}