如何使用Validator验证表单数据

<?php

namespace App\Http\Controllers;

 //引入验证类
use Validator;
 use App\Models\Post;
use Illuminate\Http\Request;

class PostController extends Controller
{
/**
 * Display a listing of the resource.
 *
 * @return \Illuminate\Http\Response
 */
public function index()
{
    //
    $post = Post::all();

    return view('post.index',compact('post'));
}

/**
 * Show the form for creating a new resource.
 *
 * @return \Illuminate\Http\Response
 */
public function create()
{
    //
    return view('post.create');
}

/**
 * Store a newly created resource in storage.
 *
 * @param  \Illuminate\Http\Request  $request
 * @return \Illuminate\Http\Response
 */
public function store(Request $request)
{
    //
    //数据验证
 $validator = Validator::make($request->all(), [
        'title' => 'required|max:255',
        'content' => 'required',
    ]);

    if ($validator->fails()) {
        return redirect('post/create')
            ->withErrors($validator)
            ->withInput();
    }
    $post = new Post;

    $post->title = $request->title;
    $post->content = $request->content;
    $post->user_id = 1;

    $post->save();
}