如何在Laravel中实现数据验证

php artisan make:request StorePostRequest

// app/Http/Requests/StorePostRequest.php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class StorePostRequest extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    public function authorize()
    {
        // 比如，只有管理员才能创建文章
        // return auth()->user()->isAdmin();
        return true; // 暂时设置为true，表示任何用户都可以
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        return [
            'title' => 'required|unique:posts|max:255',
            'body' => 'required',
            'category_id' => 'required|exists:categories,id',
            'tags' => 'array',
            'tags.*' => 'exists:tags,id' // 验证数组中的每个元素
        ];
    }

    /**
     * Get custom messages for validator errors.
     *
     * @return array
     */
    public function messages()
    {
        return [
            'title.required' => '文章标题不能为空哦！',
            'title.unique' => '这个标题已经被人用了，换一个吧。',
            'body.required' => '文章内容总得有点什么吧？',
            // ... 更多自定义消息
        ];
    }
}

// app/Http/Controllers/PostController.php

namespace App\Http\Controllers;

use App\Http\Requests\StorePostRequest; // 引入你创建的请求
use App\Models\Post;

class PostController extends Controller
{
    /**
     * Store a newly created resource in storage.
     *
     * @param  \App\Http\Requests\StorePostRequest  $request
     * @return \Illuminate\Http\Response
     */
    public function store(StorePostRequest $request)
    {
        // 如果验证失败，Laravel会自动重定向回上一个页面，并闪存错误消息。
        // 如果验证通过，你就可以安全地访问$request中的数据了
        $validated = $request->validated(); // 获取所有通过验证的数据

        $post = Post::create($validated);

        return redirect()->route('posts.show', $post->id)->with('success', '文章发布成功！');
    }
}

use Illuminate\Support\Facades\Validator;
use Illuminate\Http\Request;

public function store(Request $request)
{
    $validator = Validator::make($request->all(), [
        'title' => 'required|unique:posts|max:255',
        'body' => 'required',
    ], [
        'title.required' => '标题是必填的。',
        'body.required' => '内容不能空着。'
    ]);

    if ($validator->fails()) {
        // 验证失败，你可以手动处理错误，比如返回JSON响应或重定向
        return redirect('post/create')
                    ->withErrors($validator)
                    ->withInput();
        // 或者
        // return response()->json(['errors' => $validator->errors()], 422);
    }

    // 验证通过
    $validated = $validator->validated();
    // ... 处理数据
}

use Illuminate\Http\Request;

public function store(Request $request)
{
    $validated = $request->validate([
        'title' => 'required|unique:posts|max:255',
        'body' => 'required',
    ], [
        'title.required' => '标题是必填的。',
        'body.required' => '内容不能空着。'
    ]);

    // 验证通过，数据已在$validated中
    // ... 处理数据
}

$request->validate([
    'email' => 'required|email',
    'password' => 'required|min:8',
], [
    'email.required' => '邮箱地址是必填的。',
    'email.email' => '请填写一个有效的邮箱格式。',
    'password.min' => '密码至少需要 :min 个字符。', // :min 会被替换成实际的最小值
]);

// app/Http/Requests/StorePostRequest.php
public function messages()
{
    return [
        'title.required' => '文章标题不能为空哦！',
        'title.unique' => '这个标题已经被人用了，换一个吧。',
        'body.required' => '文章内容总得有点什么吧？',
    ];
}

use Illuminate\Validation\Rule;

$request->validate([
    'coupon_code' => [
        'required',
        function ($attribute, $value, $fail) {
            if ($value === 'INVALID_CODE') {
                $fail('优惠码无效。');
            }
            // 假设这里会去数据库查询优惠码是否真实有效
            // if (! Coupon::isValid($value)) {
            //     $fail('优惠码不存在或已过期。');
            // }
        },
    ],
]);

php artisan make:rule IsJsonString

// app/Rules/IsJsonString.php

namespace App\Rules;

use Illuminate\Contracts\Validation\Rule;

class IsJsonString implements Rule
{
    /**
     * Determine if the validation rule passes.
     *
     * @param  string  $attribute
     * @param  mixed  $value
     * @return bool
     */
    public function passes($attribute, $value)
    {
        // 尝试解码JSON字符串，如果失败则返回false
        json_decode($value);
        return (json_last_error() == JSON_ERROR_NONE);
    }

    /**
     * Get the validation error message.
     *
     * @return string
     */
    public function message()
    {
        return 'The :attribute must be a valid JSON string.';
    }
}

use App\Rules\IsJsonString;

$request->validate([
    'data_payload' => ['required', new IsJsonString()],
]);