雄辩的关系（Laravel 5.4）-Java 学习之路

我正在制作 Laravel 5.4 应用程序，但我很难弄清楚如何用 eloquent relationships 构建数据 .

这是我的模型以及我希望它们如何相关：

School →有 class ，用户和活动
User →可以属于学校 . 可以有课程和会话（有案例）
Class →属于学校 . 有用户和科目 . 可以做作业
Subject →属于一个 class
Session →属于用户 . 可以有案例
Case →属于某个会话
Event →属于学校
Homework →属于一个 class

我应该如何在我的Laravel 5.4项目中使用雄辩的关系函数（belongsTo，hasMany等）来构建它？

3 回答

假设类，用户和事件模型具有属性school_id，并且您使用的主键是相应模型的ID，您的类，用户，事件和学校模型应如下所示 .

学校

class School extends Model
{
public function users(){
    return $this->hasMany('App\User');
}

public function classes(){
    return $this->hasMany('App\Class');
}

public function sessions(){
    return $this->hasMany('App\Session');
}
}

用户

class User extends Model
{
public function school(){
    return $this->belongsTo('App\School');
}

public function classes(){
    return $this->hasMany('App\Class');
}

public function events(){
    return $this->hasMany('App\Event');
}
}

类

class Class extends Model
{
public function school(){
    return $this->belongsTo('App\School');
}

public function users(){
    return $this->hasMany('App\User');
}

public function subjects(){
    return $this->hasMany('App\Subject');
}
public function homeworks(){
    return $this->hasMany('App\Homework');
}
}

事件

class Class extends Model
{
public function school(){
    return $this->belongsTo('App\School');
}

}

您可以使用这些关系来定义具有链接功能的查询 . 例如如果你想获得与学校相关的所有事件，其id属性等于$ id，你可以写，

$events = App\School::find($id)->events;

Laravel Documentation解释得很好

回复于 2024-04-27T22:52:23+08:00

正确的方法是

SCHOOL

public function classes()
{
    return $this->hasMany('App\Class');
}

public function users()
{
    return $this->hasMany('App\User');
}

public function events()
{
    return $this->hasMany('App\Event');
}

CLASS

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

public function subjects()
{
    return $this->hasMany('App\Subject');
}

public function homeworks()
{
    return $this->hasMany('App\Homework');
}


public function users()
{
    return $this->belongsToMany('App\User','class_users','class_id','user_id');
    // this should be many to many because users can also have many classes
}

USER

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

public function classes()
{
    return $this->belongsToMany('App\Class','class_users','user_id','class_id');
    // this should be many to many as explained to class
}

public function sessions()
{
    return $this->belongsToMany('App\Session','session_users','user_id','session_id');
    // like classes do, this should be many to many relationship because sessions can also have many users
}

SUBJECT

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

SESSION

public function users()
{
    return $this->belongsToMany('App\User','session_users','session_id','user_id');
    // should be many to many as well
}

public function cases()
{
    return $this->hasMany('App\Case');
}

CASE

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

EVENT

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

HOMEWORK

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

回复于 2024-04-27T22:52:23+08:00

-1

创建学校模型和基础表后，就可以创建关系了 . 打开School模型并创建一个名为classes，users和events的公共方法;在它内部引用hasMany方法：

学校：

class School extends Model {

  public function classes()
  {
    return $this->hasMany('App\Class');
  }
  public function users()
  {
    return $this->hasMany('App\User');
  }
  public function events()
  {
    return $this->hasMany('App\Event');
  }

}

用户：

class User extends Model {

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

    public function classes(){
        return $this->hasMany('App\Class');
    }

    public function sessions(){
        return $this->hasMany('App\Session');
    }

}

分类：

class Class extends Model {

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

    public function users(){
        return $this->hasMany('App\User');
    }

    public function subjects(){
        return $this->hasMany('App\Subject');
    }

    public function homeworks(){
        return $this->hasMany('App\Homework');
    }

}

学科：

class Subject extends Model {

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

}

Session ：

class Session extends Model {

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

    public function cases(){
        return $this->hasMany('App\Case');
    }

}

案件：

class Case extends Model {

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

}

事件：

class Event extends Model {

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

}

家庭作业：

class Homework extends Model {

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

}

有关hasMany关系的更多详细信息，请查看此处的链接：EasyLaravelBook

回复于 2024-04-27T22:52:23+08:00

雄辩的关系（Laravel 5.4）

3 回答

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