数据库访问类链式查询方法

一、链式查询方法

1.whereBetween()在范围之间查询

控制器:home.php

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
Class Home extends Controller{
    //whereBetwen在范围内查询
    public function between(){
        $res = DB::table('staff')->select('id','name','age')->whereBetween('age',[20,25])->get();
        echo '<pre>';
        print_r($res);
    }
}

路由：web.php

<?php
use Illuminate\Support\Facades\Route;
Route::get('/home/between','Home@between');

2.whereIn()在指定数组中查询

控制器:home.php

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
Class Home extends Controller{
    //whereIn
    public function in(){
        $res = DB::table('staff')->whereIn('id',[1002,1050])->get();
        echo '<pre>';
        print_r($res);
    }
}

路由：web.php

<?php
use Illuminate\Support\Facades\Route;
Route::get('/home/in','Home@in');

3.orWhere() 或查询

控制器:home.php

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
Class Home extends Controller{
    //orWhere
    public function whereor(){
        $res = DB::table('staff')->where('id',1002)->Orwhere('id',1007)->get();
        echo '<pre>';
        print_r($res->toArray());
    }
}

路由：web.php

<?php
use Illuminate\Support\Facades\Route;
Route::get('/home/whereor','Home@whereor');

4.join() 多表查询

控制器:home.php

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
Class Home extends Controller{
    //join查询
    public function join(){
        $res = DB::table('staff')->join('user','staff.name','=','user.name')->get();
        echo '<pre>';
        print_r($res);
    }
}

路由：web.php

<?php
use Illuminate\Support\Facades\Route;
Route::get('/home/join','Home@join');

二、中间件

• 定义中间件：Mycheck.php

<?php
namespace App\Http\Middleware;
use Illuminate\Http\Request;
use Closure;
/*
中间件
固定格式
*/
class Mycheck{
    public function handle(Request $request,Closure $next){
        $a = 3;
        $b = 5;
        if($a+$b === 8){
            return response('a+b='.($a+$b),200);
        }
        return $next($request);
    }
}

• 注册中间件：Kernel.php

<?php
namespace App\Http;
use Illuminate\Foundation\Http\Kernel as HttpKernel;
class Kernel extends HttpKernel
{
protected $routeMiddleware = [
//注册中间件
        'mycheck' => \App\Http\Middleware\Mycheck::class,
    ];
}

• 触发中间件：web.php

<?php
use Illuminate\Support\Facades\Route;
Route::get('/home/join','Home@join')->middleware('mycheck');