laravel 操作数据库

建立student控制器，控制器代码

namespace App\Http\Controllers;

use Illuminate\Support\Facades\DB;

class StudentController extends Controller
{

    //添加
    public function addstudent(){
        $student = DB::insert('insert into student(name,age,gender) values(?,?,?)',['张三',12,2]);
        var_dump($student);//成功返回bloo值true
    }

    //获取
    public function getall(){
//       $student = DB::select('select * from student');
       $student = DB::select('select * from student where id>?',[1]);
        return $student;//数组
    }

    //修改
    public function updstudent(){
        $student = DB::update('update student set age= ? where name=?',[10,'张三']);
        var_dump($student);//成功返回bloo值true
    }

    //修改
    public function delstudent(){
        $student = DB::delete('delete from student where id=?',[10]);
        var_dump($student);
    }
}

注意 laravel中return true会报错：

(1/1) UnexpectedValueException

The Response content must be a string or object implementing __toString(), "boolean" given.