Question

我正在尝试运行hasMany，但我真的不知道为什么我没有得到任何结果！两个表：Company，Joborder，每个作业都有一个我想使用的laravel中的EmiratesTo关系获取的公司名称和地址

   <?php
    namespace App;

class Company extends Model
{
    protected   $table = 'company';
      protected $primaryKey = 'company_id';

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

}

我的工作订单页面

<?php

namespace App;

class Joborder extends Model
{
    protected $table = "joborder";
    public $primaryKey  = "joborder_id";
         protected $dates = [
             'start_date',
        'created_at',
        'updated_at'
    ];
    public function company(){
        return $this->belongsTo('App\Company');
    }

    }

这是PageController：

       public function joblist() {
           $joblist = Joborder::all();
          $newInstance = new Joborder;
           $company = $newInstance->company();


            dd($company->name);
             dd($joblist);
            return view('pages.joblist')->with('jobs',$joblist);
          }

这是我页面运行后的第dd位

BelongsTo {#217 ▼
  #foreignKey: "company_id"
  #otherKey: "company_id"
  #relation: "company"
  #query: Builder {#218 ▶}
  #parent: Joborder {#205 ▼
    #table: "joborder"
    +primaryKey: "joborder_id"
    #dates: array:3 [▼
      0 => "start_date"
      1 => "created_at"
      2 => "updated_at"
    ]
    #guarded: array:1 [▼
      0 => "id"
    ]
    #fillable: []
    #connection: null
    #keyType: "int"
    #perPage: 15
    +incrementing: true
    +timestamps: true
    #attributes: []
    #original: []
    #relations: []
    #hidden: []
    #visible: []
    #appends: []
    #dateFormat: null
    #casts: []
    #touches: []
    #observables: []
    #with: []
    #morphClass: null
    +exists: false
    +wasRecentlyCreated: false
  }
  #related: Company {#212 ▼
    #table: "company"
    #primaryKey: "company_id"
    #guarded: array:1 [▼
      0 => "id"
    ]
    #fillable: []
    #connection: null
    #keyType: "int"
    #perPage: 15
    +incrementing: true
    +timestamps: true
    #attributes: []
    #original: []
    #relations: []
    #hidden: []
    #visible: []
    #appends: []
    #dates: []
    #dateFormat: null
    #casts: []
    #touches: []
    #observables: []
    #with: []
    #morphClass: null
    +exists: false
    +wasRecentlyCreated: false
  }
}

我在company中有company_id作为pkey，在joborder中具有fkey 感谢您的帮助！

Answer 1

您应该致电

$company = $newInstance->company()->get();

代替

$company = $newInstance->company();

在PageController:jobList中。
现在，您正在通过关系数据本身来重现关系本身。

或者，您可以将company作为属性来访问，该属性应自动返回相关数据，而不是关系本身：

$company = $newInstance->company;

Answer 2

您需要在两个关系中同时指定foreignKey和localKey，因为您没有ID作为主键

公司模型

public function jobs() {
     return $this->hasMany('App\Joborder','company_id','company_id');
}

工作模式

public function company(){
     return $this->belongsTo('App\Company', 'company_id', 'company_id');
}

现在这样获取

public function joblist() {
    $joblist = Joborder::with('company')->all();

    dd($joblist);

    return view('pages.joblist')->with($joblist);
}

如果您需要提取公司的选定字段，则可以在急切加载$query->select('name', 'address');中指定它

public function joblist() {
    $joblist = Joborder::with(['company' => function($query){
                         $query->select('name', 'address');
               }])->get();

    return view('pages.joblist')->with($joblist);
}

在刀片服务器中，您可以像这样访问公司数据

@foreach($joblist as $job)
   @if($job->company)
      {{$job->company->name}}
      {{$job->company->address}}
   @endif
@endforeach

Answer 3

尝试类似的方法

public function joblist() {
    $joblist = Joborder::with('company')->get();         
    return view('pages.joblist')->with('jobs',$joblist);
}

确保公司表中有工作清单的ID。还要检查外键名称，否则您必须通过joborder_id或任何外键名称：

public function company(){
    return $this->belongsTo('App\Company', 'joborder_id');
}

Laravel AboutTo关系不返回值

3 个答案: