laravel学习笔记(二)

• 路由

HTTP方法:支持http1.1中所有类型传参方式,get,post,put,delete,options,patch

Route::get($url,$callback);

路由参数:

Route::get('user/{id}',function($id){return 'userid:'.$id});

路由分组:

Route::group(['prefix'=>'admin'],function(){
　　Route::get('users',function(){
　　//"admin/users"
　　})
});

绑定模型:

　//默认对应关系:user=>表users ,主键=>id

　Route::get('api/users/{user}',function(App\user $user){ 　　return $user->email; })

• 创建控制器

php artisan make:controller PostController

相关：

php artisan 
php artisan help make:controller

• 创建路由(文章模块)

routes/web.php

//文章列表页
Route::get('/posts','\App\Http\Controllers\PostController@index');
//文章创建
Route::get('/posts/create','\App\Http\Controllers\PostController@create');
Route::post('/posts','\App\Http\Controllers\PostController@store');
//文章详情页
Route::get('/posts/{post}','\App\Http\Controllers\PostController@show');
//文章编辑
Route::get('/posts/{post}/edit','\App\Http\Controllers\PostController@edit');
Route::put('/posts/{post}','\App\Http\Controllers\PostController@update');
//文章删除
Route::get('/posts/delete','\App\Http\Controllers\PostController@delete');

• 创建控制器具体方法

位置：app/Http/Controllers/PostController.php

public function index(){
     return view("post/index");  //模版渲染
}
public function show(){
    return view("post/show");
}

public function delete(Post $post){
    $post->delete();
    return(redirect('posts/'));　　//页面跳转
}

• 创建模板

在 resources/views/下创建post文件夹，在其中创建对应的 *.blade.php ，eg: resources/views/post/create.blade.php

• 模版语法

{{}}
@if @endif
@foreach @endforeach

注：参数传递 compact

• 继承模型

extends 引入公共模板 @extends('layout.main')

section 进行填充 @section("content") @endsection

yield 定义填充 @yield("content")

引入视图 include(模型再细化) @include('layout.footer')

• 数据表

migrate ,对所有的表的操作都以日志来记录，便于协同开发

表名(名词+s)

外键(表名_键名)

时间(created_at,updated_at)

• 数据库迁移

创建posts表: 

php artisan make:migration create_posts_table

自动创建 database/migrations/2018_09_29_072923_create_posts_table.php

Q: SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes (SQL: alter table `users` add unique `users_email_unique`(`email`))
A: app/Providers/AppServiceProvider.php boot()
use Illuminate\Support\Facades\Schema;
Schema::c(250);

自动检查sqllog并执行:

php artisan migrate

• 文章模块模型

ORM Laravel 的 Eloquent ORM 提供了漂亮、简洁的 ActiveRecord 实现来和数据库交互。

每个数据库表都有一个对应的「模型」用来与该表交互。你可以通过模型查询数据表中的数据，并将新记录添加到数据表中。

创建模型：

 php artisan make:model Post

生成: app/Post.php //对应数据表posts,可通过 private $table = 'newtableName'; 来修改默认表名

about: php artisan help make:model

• thinker 常驻进程

php artisan tinker

add:
$post = new \App\Post();
$post->title="this is post';
$post->content="this is content';
$post->save();
select:
$post->find(2); //  \App\Post::find(2); 仅支持主键查找
\App:Post::where('title','zhangsan')->first();
\App:Post::where('title','zhangsan')->get();
modify
$post = \App\Post::find(2);
$post->title = 'hahazhangsan';
$post->save();
delete:
$post->delete();

修改时区(默认英国时区)
config/app.php
'timezone' => 'Asia/Shanghai', //UTC

• 数据填充thinker

参考：https://github.com/fzaninotto/Faker

创建工厂，目录：database/factories/ModelFactory.php

$factory->define(App\Post::class,function(Faker\Generator $faker) {
    return [
        'title'=>$faker->words($nb = 3, $asText = true),
        'content'=>$faker->text($maxNbChars = 100)
    ];
});

在tinker中(新创建的工厂记得重启tinker后才可生效) 

php artisan tinker
factory(App\Post::class,20)->make();        //仅显示,未真正添加至库中
factory(App\Post::class,20)->create();      //创建并写入库

• 分页

参考：https://laravel-china.org/docs/laravel/5.4/pagination/1260

//$lists = Post::orderBy('created_at','desc')->get();
$lists = Post::orderBy('created_at','desc')->paginate(5);
// $lists = [['title'=>'nana'],['title'=>'nana2'],['title'=>'nana'],['title'=>'nana2'],['title'=>'nana'],['title'=>'nana2']];

{{$posts->links()}}

• 辅助函数

参考：https://laravel-china.org/docs/laravel/5.4/helpers/1252 ,eg:str_limit()
栗子：html原生输出:{!! str_limit($post->content,30,'...') !!}