我有一张 table tanks

+----+----------+-------+-------+
| id | capacity | model | width |
+----+----------+-------+-------+
|  1 |     1000 |    15 |   960 |
|  2 |    50000 |    30 |   200 |
|  3 |      100 |    15 |    12 |
|  4 |    80000 |    40 |   100 |
|  5 |     1000 |    30 |   123 |
|  6 |      500 |     5 |  1213 |
|  7 |     1000 |    22 |  2234 |
+----+----------+-------+-------+

然后我在我的表中添加了 unique 属性

ALTER TABLE `tanks`
ADD UNIQUE `capacity_model_width` (`capacity`, `model`, `width`);

我存储值的函数是这样的

public function store(Request $request) {

        $image = new tank();

        $this->validate($request, [
                'capacity' => 'required|numeric',
                'model' => 'required|numeric',
                'width' => 'required|numeric',
            ]                
                );

        $image->capacity = $request->capacity;
        $image->model = $request->model;
        $image->width = $request->width;
        $image->save();

        return redirect()->route('tank.index')
                        ->with('success', 'Tank created successfully');
    }

现在当我在下方插入时显示错误

Integrity constraint violation: 1062 Duplicate entry 
'1000-22-2234' for key 'capacity_model_width'

如果它们是唯一的，我需要在我的提交中显示错误消息。我是 Laravel 的新手，如何在存储函数中添加自定义验证和错误消息

最佳答案

将此添加到您的代码中

我们将首先检查我们需要的字段是否存在，然后我们将它们连接起来并将它们添加到请求中。从那里我们现在可以运行我们独特的验证

public function store(Request $request) {
    $image = new tank();
    //Check to see if fields exist then validate after concatenation

    if(isset($request->capacity) && isset($request->model) && isset($request->width) ){
         $request->request->add(['my_key' => ['capacity' => $request->capacity, 'model' => $request->model, 'width' => $request->width] ]);
    }
    $this->validate($request, [
            'capacity' => 'required|numeric',
            'model' => 'required|numeric',
            'width' => 'required|numeric',
            'my_key' => 'required|uniqueCapacity',
        ]                
            );

    $image->capacity = $request->capacity;
    $image->model = $request->model;
    $image->width = $request->width;
    $image->save();

    return redirect()->route('tank.index')
                    ->with('success', 'Tank created successfully');
}

添加自定义验证器

首先访问您的 AppServiceProvider 并添加以下内容

class AppServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        Validator::extend('uniqueCapacity', function ($attribute, $value, $parameters, $validator) {
       $value_array = explode("-", $value);
        $items = DB::select("SELECT count(*) as aggregate FROM tanks WHERE capacity ='$value_array[0]' AND model='$value_array[1]' AND width='$value_array[2]' "); 
        $number=$items[0]->aggregate;
        if ($number > 0) {
            return false;
        } else {
            return true;
        }
        });
    }

    /**
     * Register the service provider.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}

关于php - 关于laravel中多个字段的唯一性的自定义验证，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/42949968/