如何在 PHP Laravel 中验证失败时显示错误消息

Question

我卡在表单验证中显示一条消息。

这是我的代码：

class InputController extends Controller
{
    public static function save(Request $request)
    {
        //Get input values to variables respectively
        $First_Name = $request->input('First_Name');
        $Last_Name = $request->input('Last_Name');
        $Email = $request->input('Email');
        $Credit_Card = $request->input('Credit_Card');
        $Password = $request->input('Password');

        //Rules for each field
        $rules = [
            'First_Name' => ['required', 'string'],
            'Last_Name' => ['required', 'string'],
            'Email' => ['required', 'string'],
            'Credit_Card' => ['required', 'string'],
            'Password' => ['required', 'string']
        ];

        //Validator variable
        $valid = Validator::make($request->all(),$rules);

        //Insert information into SQL table
        $customer = new CustomersTable;
        $customer->First_Name = $First_Name;
        $customer->Last_Name = $Last_Name;
        $customer->Email = $Email;
        $customer->Credit_Card = $Credit_Card;
        $customer->Password = Hash::make($Password);

        $customer->save();

        //If validation fails, pop out a message or else view localhost/submit
        if ($valid -> failed())
        {
            dd("Error! Some of the required information are empty");
        }
        else
        {
            return view('submit');
        }
    }
}

在下面：

if ($valid -> failed())
{
    dd("Error! Some of the required information are empty");
}
else
{
    return view('submit');
}

，当我让表单中的每个字段（First_Name，Last_Name，...）为空并单击按钮发布时，验证应该失败并且页面应该显示

"Error! Some of the required information are empty"

但是却弹出了SQL的错误：

SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'First_Name' cannot be null

，表示跳转到“else”语句。 谁能帮我解释一下？

Answer 1

您必须在插入数据之前输入此代码

if ($valid -> failed())
{
    dd("Error! Some of the required information are empty");
}

你的代码应该是

//Validator variable
    $valid = Validator::make($request->all(),$rules);
    if ($valid -> failed())
    {
        dd("Error! Some of the required information are empty");
    }
    else
    {
        //Get input values to variables respectively
        $First_Name = $request->input('First_Name');
        $Last_Name = $request->input('Last_Name');
        $Email = $request->input('Email');
        $Credit_Card = $request->input('Credit_Card');
        $Password = $request->input('Password');

        //Insert information into SQL table
        $customer = new CustomersTable;
        $customer->First_Name = $First_Name;
        $customer->Last_Name = $Last_Name;
        $customer->Email = $Email;
        $customer->Credit_Card = $Credit_Card;
        $customer->Password = Hash::make($Password);

        $customer->save();
        return view('submit');
   }

Answer 2

我认为这是因为您在验证之前将请求值分配给变量。试试这个：

class InputController extends Controller
{
    public static function save(Request $request)
    {
       
        $request->validate([
            'First_Name' => ['required', 'string'],
            'Last_Name' => ['required', 'string'],
            'Email' => ['required', 'string'],
            'Credit_Card' => ['required', 'string'],
            'Password' => ['required', 'string']
        ]);


        //Get input values to variables respectively
        $First_Name = $request->input('First_Name');
        $Last_Name = $request->input('Last_Name');
        $Email = $request->input('Email');
        $Credit_Card = $request->input('Credit_Card');
        $Password = $request->input('Password');

        //Insert information into SQL table
        $customer = new CustomersTable;
        $customer->First_Name = $First_Name;
        $customer->Last_Name = $Last_Name;
        $customer->Email = $Email;
        $customer->Credit_Card = $Credit_Card;
        $customer->Password = Hash::make($Password);

        $customer->save();

        //If validation fails, pop out a message or else view localhost/submit
        if ($valid -> failed())
        {
            dd("Error! Some of the required information are empty");
        }
        else
        {
            return view('submit');
        }
    }
}

Answer 3

if ($valid->fails())
{
   return redirect()->back()->withErrors($valid)->withInput();
}

并在刀片模板中显示以下代码的错误

@if ($errors->has('First_Name'))
    <span class="invalid-feedback">
        <strong>{{ $errors->first('First_Name') }}</strong>
    </span>
@endif