导出PDF时出现Attempt to read property 'id' on bool错误的解决咨询

点击导出PDF按钮时出现错误：Attempt to read property 'id' on bool，已调试控制器中的$data变量，确认能返回指定ID的记录。相关代码如下：

PDFController.php #

<?php

namespace App\Http\Controllers;

use App\Models\Contract;
use Illuminate\Http\Request;
use Barryvdh\DomPDF\Facade\Pdf;
use App\Models\User;
use Filament\Infolists\Infolist;

class PDFController extends Controller
{
    public function downloadpdf($id)
    {
        $contract = Contract::with(['surveys', 'surveys.surveyors', 'surveys.assets'])
            ->where('id', $id)
            ->first();

        $users = User::all();

        $data = [
            'date' => $contract->selesai_kontrak,
            'users' => $users,
            'contract' => $contract
        ];

        dd($data);

        $pdf = PDF::loadView('contractPDF', $data);

        return $pdf->download('ContractDetails.pdf');
    }
}

contractPDF.blade.php #

<!DOCTYPE html>
<html>

<head>
    <title>Contract Details</title>
</head>

<body>
    <h1>Contract Details</h1>
    <p>Date: {{ $date }}</p>

    <div>
        <h2>Contract ID: {{ $contract->id }}</h2>
        <p>Pemberi Tugas: {{ $contract->pemberi_tugas }}</p>
        <p>Jenis Industri: {{ $contract->industries->type }}</p>
        <p>Tujuan Kontrak: {{ $contract->contract_types->type }}</p>
        <p>Lokasi Proyek: {{ $contract->lokasi_proyek }}</p>

        @foreach ($contract->surveys as $survey)
            <h3>Survey ID: {{ $survey->id }}</h3>
            <p>Surveyor: {{ $survey->surveyors->name }}</p>
            <p>Pemilik Aset: {{ $survey->pemilik_aset }}</p>
            <p>Tanggal Survey: {{ $survey->tanggal_survey }}</p>
            <p>Jenis Aset: {{ $survey->assets->type }}</p>
            <p>Keterangan Aset: {{ $survey->keterangan_aset }}</p>
            <img src="{{ asset('storage/' . $survey->gambar_aset) }}" alt="Gambar Aset">
            <p>Harga Aset: Rp. {{ number_format($survey->harga_aset, 0, '.', '.') }}</p>
        @endforeach
    </div>
</body>

</html>

Contract.php #

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\Relations\HasOne;
use Illuminate\Database\Eloquent\Relations\BelongsTo;

class Contract extends Model
{
    use HasFactory;

    protected $fillable = [
        'surveyors_id',
        'surveys_id',
        'pemberi_tugas',
        'industries_id',
        'contract_types_id',
        'lokasi_proyek',
        'tanggal_kontrak',
        'selesai_kontrak',
        'status_kontrak',
        'durasi_kontrak',
        'is_available',

    ];

    public function surveys(): HasOne
    {
        return $this->hasOne(Survey::class);
    }

    public function surveyors(): BelongsTo
    {
        return $this->belongsTo(Surveyor::class);
    }

    public function contract_types(): BelongsTo
    {
        return $this->belongsTo(ContractType::class);
    }

    public function industries(): BelongsTo
    {
        return $this->belongsTo(Industry::class);
    }

    public function setStatusKontrakAttribute($value)
    {
        $this->attributes['status_kontrak'] = $value;

        if ($value === 'In Progress') {
            $this->attributes['is_available'] = 1;
        } elseif ($value === 'Selesai' || $value === 'Batal') {
            $this->attributes['is_available'] = 0;
        }
    }
}

1. 关联关系与视图遍历不匹配（核心错误） #

Contract模型中surveys定义为HasOne（一对一），但视图里用@foreach遍历该关联。一对一关联返回的是单个模型对象，而非集合，遍历对象时会被当作布尔值处理，触发read property 'id' on bool错误。

分情况修复： #

• 如果是真·一对一关系：
  移除视图中的@foreach循环，直接访问关联属性，同时添加空判断：

  @if($contract->surveys)
      <h3>Survey ID: {{ $contract->surveys->id }}</h3>
      <p>Surveyor: {{ $contract->surveys->surveyors->name }}</p>
      <p>Pemilik Aset: {{ $contract->surveys->pemilik_aset }}</p>
      <!-- 其他属性同理 -->
  @endif
  

• 如果实际是一对多关系：
  修改Contract模型的关联定义：

  public function surveys(): HasMany
  {
      return $this->hasMany(Survey::class);
  }
  

  同时核对数据库：确保surveys表存在contract_id外键（当前模型$fillable中的surveys_id可能是外键方向搞反了，需修正）。

2. 空关联的防御性处理 #

即使$contract存在，其关联的industries、contract_types等可能为空，直接访问属性会报错。

• 视图层处理：使用可选链式调用?->和默认值：

  <p>Jenis Industri: {{ $contract->industries?->type ?? 'N/A' }}</p>
  <p>Tujuan Kontrak: {{ $contract->contract_types?->type ?? 'N/A' }}</p>
  

• 模型层处理：给关联添加默认值，避免空对象报错：

  public function industries(): BelongsTo
  {
      return $this->belongsTo(Industry::class)->withDefault(['type' => 'N/A']);
  }
  
  public function contract_types(): BelongsTo
  {
      return $this->belongsTo(ContractType::class)->withDefault(['type' => 'N/A']);
  }
  

3. 控制器优化 #

• 添加404异常处理，避免ID不存在时的错误：

  $contract = Contract::with(['surveys', 'surveys.surveyors', 'surveys.assets', 'industries', 'contract_types'])
      ->where('id', $id)
      ->firstOrFail(); // 找不到记录直接返回404
  

• 预加载industries和contract_types，避免N+1查询问题。
• 移除调试用的dd($data)，确保代码正常执行。

4. 数据库外键核对 #

• 一对一关系：确认contracts表的surveys_id关联到surveys表的id。
• 一对多关系：确认surveys表的contract_id关联到contracts表的id。

内容的提问来源于stack exchange，提问作者fajar sakti