Untitled

<?php
session_start();
include("models/db.php");
include("controllers/Users.php");
echo ("memory limit: " . ini_get("memory_limit") . "<br />");
echo ("memory usage: " . round(memory_get_usage(true)/1048576,2) . "Mb (" .
memory_get_usage(true) . " bytes)<br />");


if(($_SERVER['REQUEST_METHOD'] == 'POST') && isset($_POST["signin"])){

   $object2 = new Users;
   $object2->login($_POST["username"],$_POST["password"]);

}

?>

<!DOCTYPE html>
<html>
    <head>
        <title>Login</title>
        <?php include("includes/inc.style.php")?>
    </head>
    <body>
        <div class="container">
            <div class="row login-form-wrapper">
                    <form  class="login-form" action="" method="post" >
                    <div class="form-group"><label for="username">Логин</label><input class="form-control" id="username" type="text" name="username"></div>
                <div class="form-group"><label for="password">Пароль</label><input class="form-control" id="password" type="password" name="password"></div>
                <input class="form-control btn btn-primary" type="submit"  name ="signin" value="Войти">
                <a href="signupform.php">Dign up</a>
            </form>
            </div>
        </div>
</body>

<?php
class Users extends DB{
    function set($username , $password , $email){
        return $this->insert($username , $password , $email);
    }
    function login($username , $password){
         return $this->login($username , $password );
    }
}

<?php
class DB{
    var $conn;

    function __construct(){
        $this->conn=new mysqli("localhost","root","","Blog");
        if($this->conn->connect_error){
            echo "DB connection error" . $this->conn->connect_error;
        }
        else{
            echo "Connected to db succesfully";
        }
    }

    function login($username , $password){
       echo memory_get_usage();
       $sql="SELECT * from users where username='$username' and password='$password'" ;
        $result=$this->conn->query($sql);
        if ($result->num_rows > 0) {
            while($row = $result->fetch_assoc()) {
                $_SESSION["username"]=$row["username"];
            }
            echo "Success"; //header('Location: post_publication.php');
        } else {
             echo "Не удалось . Ошибка" .$this->conn->error;
        }


        $this->conn->close();
    }
    function insert($username , $password , $email){
        $result=$this->conn->query("INSERT INTO users VALUES('','$username','$password','$email','2')");

        if ($result === TRUE) {
            header('Location: login.php?registered=true');
        }
        else{
            $error= "Не удалось . Ошибка" .$this->conn->error;
        }
        $this->conn->close();
    }
    function __destruct(){
        if ($this->conn!==null) { $this->conn = null; }
    }


}

//function login($username , $password){
//     return $this->login($username , $password );
//}

return parent::login($username, $password);