Laravel Blade模板中数据库查询的最佳实践与value()方法详解

<td>{{format_price($mission->amount)}}</td>
@php
    $amount_to_be_collected = DB::table('shipments')
    ->select('amount_to_be_collected')
    ->where('mission_id', $mission->id)
    ->get(); // 这里是问题所在
@endphp
<td>{{format_price($amount_to_be_collected)}}</td>

// 返回一个Collection，即使mission_id唯一
$shipmentsCollection = DB::table('shipments')
    ->where('mission_id', $mission->id)
    ->get();

// 访问数据需要迭代或使用first()
if ($shipmentsCollection->isNotEmpty()) {
    $amount = $shipmentsCollection->first()->amount_to_be_collected;
}

$amount_to_be_collected = DB::table('shipments')
    ->where('mission_id', $mission->id)
    ->value('amount_to_be_collected'); // 直接返回数值或字符串

// app/Http/Controllers/MissionController.php
<?php

namespace App\Http\Controllers;

use App\Models\Mission; // 假设您有Mission模型
use Illuminate\Support\Facades\DB;
use Illuminate\Http\Request;

class MissionController extends Controller
{
    public function show(Mission $mission)
    {
        // 从数据库获取需要的数据
        $amountToBeCollected = DB::table('shipments')
            ->where('mission_id', $mission->id)
            ->value('amount_to_be_collected');

        // 将数据传递给视图
        return view('missions.show', [
            'mission' => $mission,
            'amountToBeCollected' => $amountToBeCollected,
        ]);
    }
}

<table>
    <thead>
        <tr>
            <th>任务金额</th>
            <th>待收款金额</th>
            <!-- 其他列 -->
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>{{ format_price($mission->amount) }}</td>
            {{-- 直接使用控制器传递过来的数据 --}}
            <td>{{ format_price($amountToBeCollected) }}</td>
            <!-- 其他数据 -->
        </tr>
    </tbody>
</table>