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// ルーティング
// noveltool/routes/web.php
Route::get('/create', 'Admin\NovelWritingController@add');

// コントローラー
// noveltool/app/Http/Controllers/Admin/NovelWritingController.php
public function add() {
    // return view('admin.create');
}

// routes/web.php ルーティング設定
Route::group(['prefix' => 'admin', 'as' => 'admin.', 'middleware' => 'auth'], function() {
    Route::resource('novel_writings', 'Admin\NovelWritingController');
});

// view側のURLの生成部分
route('admin.novel_writings.index'); 
route('admin.novel_writings.create');
route('admin.novel_writings.store');
route('admin.novel_writings.show', $novel->id);
route('admin.novel_writings.edit', $novel->id);
route('admin.novel_writings.update', $novel->id);
route('admin.novel_writings.destroy', $novel->id);

    public function create(Request $request, NovelWriting $novelWriting)
    {
        // 以下を追記
        // Varidationを行う
        $this->validate($request, NovelWriting::$rules);

        $novelwriting = new NovelWriting;
        $form = $request->all();
      
        // フォームから送信されてきた_tokenを削除する
        unset($form['_token']);
      
        $novelwriting->fill($form);
        $novelwriting->save();
      
        // admin/createにリダイレクトする
        return redirect('admin/create');
    }

    public function create(Request $request)
    {
        return view('admin.create');
    }

    public function store(Request $request, NovelWriting $novelWriting)
    {
            // 以下を追記
        // Varidationを行う
        $this->validate($request, NovelWriting::$rules);

        $novelwriting = new NovelWriting;
        $form = $request->all();
      
        // フォームから送信されてきた_tokenを削除する
        unset($form['_token']);
      
        $novelwriting->fill($form);
        $novelwriting->save();
        return view('admin.create');
    }

    public function store(Request $request, NovelWriting $novelWriting)
    {
            // 以下を追記
        // Varidationを行う
        $this->validate($request, NovelWriting::$rules);

        $novelwriting = new NovelWriting;
        $form = $request->all();
      
        // フォームから送信されてきた_tokenを削除する
        unset($form['_token']);
      
        $novelwriting->fill($form);
        $novelwriting->save();
        return redirect('admin/index');
    }

<?php

/*
|--------------------------------------------------------------------------
| Web Routes
|--------------------------------------------------------------------------
|
| Here is where you can register web routes for your application. These
| routes are loaded by the RouteServiceProvider within a group which
| contains the "web" middleware group. Now create something great!
|
*/
/*
Route::get('/', function () {
    return view('welcome');
});
*/

Route::group(['prefix' => 'admin', 'as'=> 'admin.', 'middleware' => 'auth'], function() {
    Route::resource('novel_writings', 'Admin\NovelWritingController');
});
Route::get('/index', 'NovelWritingController@index');
Auth::routes();
Route::get('/', 'NovelWritingController@index');

<?php

namespace App\Http\Controllers\Admin;

use App\NovelWriting;
use App\Http\Controllers\Controller;
use Illuminate\Http\Request;


class NovelWritingController extends Controller
{
    /**
     * Display a listing of the resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function index(Request $request)
    {
        $cond_title = $request->cond_title;
        if ($cond_title != '') {
        // 検索されたら検索結果を取得する
            $posts = NovelWriting::where('title', $cond_title)->get();
        }else{
        // それ以外はすべてのニュースを取得する
            $posts = NovelWriting::all();
        }
            return view('admin.novel_writings.index', ['posts' => $posts, 'cond_title' => $cond_title]);
    }

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

    /**
     * Store a newly created resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function store(Request $request)
    {
            // 以下を追記
        // Varidationを行う
        $this->validate($request, NovelWriting::$rules);

        $novelwriting = new NovelWriting;
        $form = $request->all();

        // フォームから送信されてきた_tokenを削除する
        unset($form['_token']);

        $novelwriting->fill($form);
        $novelwriting->save();
        return redirect()->route('admin.novel_writings.index');
    }

    /**
     * Display the specified resource.
     *
     * @param  \App\NovelWriting  $novelWriting
     * @return \Illuminate\Http\Response
     */
    public function show(Request $request, NovelWriting $novelWriting)
    {
        $cond_title = $request->cond_title;
        if ($cond_title != '') {
        // 検索されたら検索結果を取得する
            $posts = NovelWriting::where('title', $cond_title)->get();
        }else{
        // それ以外はすべてのニュースを取得する
            $posts = NovelWriting::all();
        }
        return view('admin.novel_writings.index', ['admin' => User::findOrFail($id)]);
    }

    /**
     * Show the form for editing the specified resource.
     *
     * @param  \App\NovelWriting  $novelWriting
     * @return \Illuminate\Http\Response
     */
    public function edit(NovelWriting $novelWriting)
    {
        return view('admin.novel_writings.edit', ['novelwriting_form' => $novelWriting]);
    }

    /**
     * Update the specified resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \App\NovelWriting  $novelWriting
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, NovelWriting $novelWriting)
    {
        // Validationをかける
        $this->validate($request, NovelWriting::$rules);
        // 送信されてきたフォームデータを格納する
        $novelWriting_form = $request->all();



        unset($novelWriting_form['remove']);
        unset($novelWriting_form['_token']);

        // 該当するデータを上書きして保存する
        $novelWriting->fill($novelWriting_form)->save();

        // $history = new History();
        // $history->news_id = $news->id;
        // $history->edited_at = Carbon::now();
        // $history->save();


      return redirect()->route('admin.novel_writings.index');
    }

    /**
     * Remove the specified resource from storage.
     *
     * @param  \App\NovelWriting  $novelWriting
     * @return \Illuminate\Http\Response
     */
    public function destroy(NovelWriting $novelWriting)
    {
        // 削除する
        $novelWriting->delete();
        return redirect()->route('admin.novel_writings.index');
    }
}

@extends('layouts.admin')
@section('title', '小説の新規作成')

@section('content')
    <div class="container">
        <div class="row">
            <div class="col-md-8 mx-auto">
                <h2>新規小説作成</h2>
                <form action="{{ route('admin.novel_writings.store') }}" method="post" enctype="multipart/form-data">

                    @if (count($errors) > 0)
                        <ul>
                            @foreach($errors->all() as $e)
                                <li>{{ $e }}</li>
                            @endforeach
                        </ul>
                    @endif
                    <div class="form-group row">
                        <label class="col-md-2">タイトル</label>
                        <div class="col-md-10">
                            <input type="text" class="form-control" name="title" value="{{ old('title') }}">
                        </div>
                    </div>
                    <div class="form-group row">
                        <label class="col-md-2">章</label>
                        <div class="col-md-10">
                            <input type="text" class="form-control" name="chapter" value="{{ old('chapter') }}">
                        </div>
                    <div class="form-group row">
                        <label class="col-md-2">節</label>
                        <div class="col-md-10">
                            <input type="text" class="form-control" name="section" value="{{ old('section') }}">
                        </div>
                    </div>
                    <div class="form-group row">
                        <label class="col-md-2">本文</label>
                        <div class="col-md-10">
                            <textarea class="form-control" name="content" rows="20">{{ old('content') }}</textarea>
                        </div>
                    </div>
                    {{ csrf_field() }}
                    <input type="submit" class="btn btn-primary" value="保存">
                </form>
            </div>
        </div>
    </div>
@endsection

@extends('layouts.admin')
@section('title', '小説の編集')

@section('content')
    <div class="container">
        <div class="row">
            <div class="col-md-8 mx-auto">
                <h2>小説編集</h2>
                <form action="{{ route('admin.novel_writings.update', $novelwriting_form->id) }}" method="post" enctype="multipart/form-data">
                    @if (count($errors) > 0)
                        <ul>
                            @foreach($errors->all() as $e)
                                <li>{{ $e }}</li>
                            @endforeach
                        </ul>
                    @endif
                    <div class="form-group row">
                        <label class="col-md-2" for="title">タイトル</label>
                        <div class="col-md-10">
                            <input type="text" class="form-control" name="title" value="{{ $novelwriting_form->title }}">
                        </div>
                    </div>
                    <div class="form-group row">
                        <label class="col-md-2" for="content">本文</label>
                        <div class="col-md-10">
                            <textarea class="form-control" name="content" rows="20">{{ $novelwriting_form->content }}</textarea>
                        </div>
                    </div>
                    <div class="form-group row">
                        <div class="col-md-10">
                            <input type="hidden" name="id" value="{{ $novelwriting_form->id }}">
                            {{ csrf_field() }}
                            <input type="submit" class="btn btn-primary" value="更新">
                        </div>
                    </div>
                </form>
                {{-- 以下を追記　
                <div class="row mt-5">
                    <div class="col-md-4 mx-auto">
                        <h2>編集履歴</h2>
                        <ul class="list-group">
                            @if ($novelwriting_form->histories != NULL)
                                @foreach ($novelwriting_form->histories as $history)
                                    <li class="list-group-item">{{ $history->edited_at }}</li>
                                @endforeach
                            @endif
                        </ul>
                    </div>
                </div>
                --}}
            </div>
        </div>
    </div>
@endsection

@extends('layouts.admin')
@section('title', '小説一覧')

@section('content')
    <div class="container">
        <div class="row">
            <h2>作成済み小説の一覧</h2>
        </div>
        <div class="row">
            <div class="col-md-4">
                <a href="{{ route('admin.novel_writings.create') }}" role="button" class="btn btn-primary">新規作成</a>
            </div>
            <div class="col-md-8">
                <form action="{{ route('admin.novel_writings.index') }}" method="get">
                    <div class="form-group row">
                        <label class="col-md-2">タイトル</label>
                        <div class="col-md-8">
                            <input type="text" class="form-control" name="cond_title" value={{ $cond_title }}>
                        </div>
                        <div class="col-md-2">
                            {{ csrf_field() }}
                            <input type="submit" class="btn btn-primary" value="検索">
                        </div>
                    </div>
                </form>
            </div>
        </div>
        <div class="row">
            <div class="admin-index col-md-12 mx-auto">
                <div class="row">
                    <table class="table table-dark">
                        <thead>
                            <tr>
                                <!--<th width="10%">ID</th>-->
                                <th width="20%">タイトル</th>
                                <!--<th width="50%">本文</th>-->
                                <!--<th width="10%">操作</th>-->
                            </tr>
                        </thead>
                        <tbody>
                             @foreach($posts as $novel)
                                <tr>
                                    <th>{{ $novel->id }}</th>
                                    <td>{{ \Str::limit($novel->title, 100) }}</td>
                                    <td>{{ \Str::limit($novel->body, 250) }}</td>
                                    <td>
                                        <div>
                                            <a href="{{ route('admin.novel_writings.edit', $novel->id) }}">編集</a>
                                        </div>
                                        <div>
                                            <a href="{{ route('admin.novel_writings.destroy', $novel->id) }}">削除</a>
                                        </div>
                                    </td>
                                </tr>
                            @endforeach
                        </tbody>
                    </table>
                </div>
            </div>
        </div>
    </div>
@endsection