在非对象上调用成员函数prepare（）（致命错误）

Question

Fatal error: Call to a member function prepare() on a non-object in G:\xampp\htdocs\live\Billing Suryas\model\DBConfig.php on line 28

<?php
    class Database
    {   
        private $host = "localhost";
        private $db_name = "new_suryas1";
        private $username = "root";
        private $password = "";
        public $conn;
        public function dbConnection()
        {
            $this->conn = NULL;    
            try
            {
                $conn = new PDO("mysql:host=" . $this->host . ";dbname=" . $this->db_name, $this->username, $this->password);
                $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 
            }
            catch(PDOException $exception)
            {
                echo "Connection error: " . $exception->getMessage();
            }

            return $conn;
        }
        public function login($usname,$uspswd)
        {
            try
            {
                $stmt =$conn->prepare("select * from users where user_name=:uname and password=:paswrd and permission='0' and delet='0'");
                $stmt->execute(array(':uname'=>$usname, ':paswrd'=>$uspswd));
                $userRow=$stmt->fetch(PDO::FETCH_ASSOC);
                if($stmt->rowCount() == 1)
                {
                    if(password_verify($uspswd, $userRow['password']))
                    {
                        $_SESSION['user_session'] = $userRow['user_id'];
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
            }
            catch(PDOException $exception)
            {
                echo $exception->getMessage();
            }
        }

    }
    ?>

This is my DBConfig.php

I can't find what is the error in my code

anyone help me please...

Answer 1

You write a class with these properties:

class Database
{   
    private $host = "localhost";
    private $db_name = "new_suryas1";
    private $username = "root";
    private $password = "";
    public $conn;

Inside a class method, variable scope is same as functions: external variables are not accessible.

To access to class properties inside a class method you have to use $this:

$this->conn = new PDO("mysql:host=" . $this->host . ";dbname=" . $this->db_name, $this->username, $this->password);
$this->conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 

(...)

$stmt = $this->conn->prepare("select * from users where user_name=:uname and password=:paswrd and permission='0' and delet='0'");

---

• Read more about variable scope
• Read more about What does the variable $this mean in PHP?