laravel5中表单的验证和提交不起作用

我有AuthController

use Illuminate'Http'Request;
use ConnectIn'Http'Requests;
class AuthController extends Controller
{
    public function getSignUp()
    {
        return view('auth.signup');
    }
    public function postSignUp(Request $request)
    {
        $this -> validate($request, [
            'username' => 'required|unique:users|alpha_dash|max:255',
            'useremail' => 'required|unique:users|email|max:255',
            'userpassword' => 'required|min:8'
            ]);
        //dd("all OK");
    }
}

我的路线是

Route::get('/', [
    'uses' => ''App'Http'Controllers'AuthController@getSignup',
    'as' => 'auth.signup',
    ]);
Route::post('/', [
    'uses' => ''App'Http'Controllers'AuthController@postSignUp',    
    ]);

signup.blade.php是

@extends ('templates.default')    
@section('register')
<div id="login-page" class="row">
      <form class="login-form" method="post" action="{{route('auth.signup')}}">
        <div class="row">
          <div class="input-field col s12 center">
            <h4>Register</h4>
            <p class="center">Join to our community now !</p>
          </div>
        </div>
        <div class="row margin">
          <div class="input-field col s12">
            <i class="mdi-social-person-outline prefix"></i>
            <input id="username" name="username" type="text">
            <label for="username" class="center-align">Username</label>
            @if($errors->has('username')) 
              <div class="error">{{$errors->first('username')}}</div>
            @endif
          </div>
        </div>
        <div class="row margin">
          <div class="input-field col s12">
            <i class="mdi-communication-email prefix"></i>
            <input id="email" name="useremail" type="email">
            <label for="email" class="center-align">Email</label>
             @if($errors->has('email')) 
              <div class="error">{{$errors->first('email')}}</div>
            @endif
          </div>
        </div>
        <div class="row margin">
          <div class="input-field col s12">
            <i class="mdi-action-lock-outline prefix"></i>
            <input id="password" name="userpassword" type="password">
            <label for="password">Password</label>
            @if($errors->has('userpassword')) 
              <div class="error">{{$errors->first('userpassword')}}</div>
            @endif
          </div>
        </div>
        <div class="row margin">
          <div class="input-field col s12">
            <i class="mdi-action-lock-outline prefix"></i>
            <input id="password-again" type="password">
            <label for="password-again">Password again</label>
          </div>
        </div>
        <input type="hidden" name="_token" value="{{ Session::token()}}">
        <div class="row">
          <div class="input-field col s12">
            <input type="submit" value="Regiter Now" class="btn waves-effect waves-light col s12"/>            
          </div>          
        </div>
      </form>
  </div>    
@stop

在这一点上，我没有收到任何错误，但无法提交表格，我的验证根本不起作用，我是不是遗漏了什么。