jucai/app/Admin/Extensions/Form/ValidateForm.php

<?php
namespace App\Admin\Extensions\Form;

use App\Admin\Extensions\Exception\ValidateException;
use Encore\Admin\Form;
use Illuminate\Support\Facades\Input;
use Symfony\Component\HttpFoundation\Response;

class ValidateForm extends Form
{
    public function getValidateInput()
    {
        $data = Input::all();

        // Handle validation errors.
        if ($validationMessages = $this->validationMessages($data)) {
            throw new ValidateException(back()->withInput()->withErrors($validationMessages));
        }

        if (($response = $this->prepare($data)) instanceof Response) {
            throw new ValidateException($response);
        }
        return $this->prepareInsert($this->updates);
    }
}