在 laravel 刀片中读取嵌套数组

Question

我正在尝试读取嵌套数组并在刀片表中显示该值。

这是我在视图中看到的数据：

{
  "sub_issue_id": 2,
  "sub_issue": "Publick speaking",
  "sub_issue_desc": "This sub issue tracks the progress related to public speaking. ",
  "sub_issue_status": 1,
  "sub_issue_main_issue_id": 1,
  "sub_issue_user_id": 1,
  "created_at": "2015-01-18 13:45:34",
  "updated_at": "2015-01-18 13:45:34",
  "main_issue": [
    {
      "main_issue_id": 1,
      "main_issue": "Commuincations",
      "main_issue_desc": "This main task tracks progress on communications. ",
      "main_issue_status": 1,
      "main_issue_user_id": 1,
      "created_at": "2015-01-18 00:20:29",
      "updated_at": "2015-01-18 00:20:29"
    }
  ]
}
{
  "sub_issue_id": 3,
  "sub_issue": "Emails",
  "sub_issue_desc": "This subissue tracks the progress related to emails. ",
  "sub_issue_status": 1,
  "sub_issue_main_issue_id": 1,
  "sub_issue_user_id": 1,
  "created_at": "2015-01-18 13:51:48",
  "updated_at": "2015-01-18 13:51:48",
  "main_issue": [
    {
      "main_issue_id": 1,
      "main_issue": "Commuincations",
      "main_issue_desc": "This main task tracks progress on communications. ",
      "main_issue_status": 1,
      "main_issue_user_id": 1,
      "created_at": "2015-01-18 00:20:29",
      "updated_at": "2015-01-18 00:20:29"
    }
  ]
}

基本上我需要读取数组“main_issue”并显示“main_issue”属性的值（在上述数据“Communications”中）

以下是我尝试过的选项：

@foreach( $subIssues as $subIssue )
            {{ $subIssue }}
            <tr>
                {{--<td>{{ $subIssue->main_issue[0]->main_issue }}</td>--}}
                {{--<td>{{ $subIssue->main_issue->first()->main_issue }} </td>--}}
                {{--<td>{{ $subIssue->main_issue->firstRow->get(0)->main_issue }} </td>--}}

Here are the model & controller code..public function SubIssue()
    {
        return $this->belongsTo('App\Models\Issues\SubIssue', 'main_issue_id','sub_issue_main_issue_id'); /**
     * Relation between sub issue and main issue
     */
    public function MainIssue()
    {
        return $this->hasMany('App\Models\Issues\MainIssue', 'main_issue_id', 'sub_issue_main_issue_id');
    }
$mainIssues = $mainIssue->where('main_issue_user_id', $id)->get();
        //dd($mainIssues->toArray());
        return view('issues.mainIssues.mainIssues', compact('mainIssues'));
    }enter code here

Answer 1

尝试以下方法：

{{ $subIssue->MainIssue->main_issue }}

考虑使用驼峰命名法命名方法，这样可以使代码更易于阅读。上一行中的 MainIssue 是 SubIssue 类的 MainIssue() 函数，如果你像 Laravel 那样遵循 PSR-1，它应该是 mainIssue()：http://www.php-fig.org/psr/psr-1/

另一个提示（来自个人经验）：不要在所有字段名中重复表名。 $main_issue->name ($main_issue->status, ect) 比 main_issue->main_issue 更容易阅读。

编辑：看起来你的键在你的关系方法中被颠倒了。 Laravel docs 表示第二个参数是外键，第三个参数是本地键。 （尽管在一对一部分的一个示例中这些术语似乎混淆了）尝试以下方法-

//In SubIssue model
mainIssue()
{
    return $this->belongsTo('App\Models\Issues\MainIssue', 'sub_issue_main_issue_id', 'main_issue_id'); 
}

//In MainIssue model
public function subIssue()
{
    return $this->hasMany('App\Models\Issues\SubIssue', 'sub_issue_main_issue_id', 'main_issue_id');
}

我发现像 'sub_issue_main_issue_id' 这样的键很难遵循，如果你使用名为 'id' 的键作为主键，而使用名为 'table_name_id' 的键（例如 main_issue_id）作为外键，你可以利用 Laravel 的约定（您不必指定在关系中使用哪些键）。

另请注意：如果您使用自己的主键，请确保在模型中设置 $primaryKey 变量：

protected $primaryKey = 'main_issue_id';